Going to the dark side here LOL
Curious to hear what anyone is doing in regards to primer seating BESIDES just pushing them in until they bottom out.
There are serious shooters who believe primer seating to bottomed out in the pocket + a certain amount of crush or preload on the primer assembly has a tuning/timing effect much like timing a trigger to a reciever/bolt assembly or even like a powder or seating ladder and in fact use the same ladders to identify the sweet spot in primer crush or preload.
If your primer is not at least touching the bottom of the pocket there's a good chance it will seat deeper under the fall of the firing pin which will at the very least give a weaker strike to the cup. If the primer is bottomed but the anvil is not at least touching the bottom of the pocket that too could affect the strength of the pin strike.
There are a few new tools out that claim to be able to seat a primer to an exact depth and apply a measurable amount of crush or preload.
What I've experienced is until you can measure the pocket accurately you are still basically guessing and until your pockets are uniformed again you are basically guessing.
In other words you may think you are getting repeatable numbers but are likely not.
Even a tool that measures application in .001"s is very susceptible to friction from variations in the pocket or the primer itself. The primer cup itself will yield from varying sidewall friction.
All the pockets I've measured tend to measure very different in depth at the center or flash hole than around the perimeter of the pocket hole on bottom. With a caliper it's easy to measure the center but up along the wall not so much.
Alpha brass appears to have a cone shaped pocket, a uniformer will cut brass off the sidewalls shortly after entry, Lapua is less tapered.
The Alpha brass is noticeably harder making uniforming noticeably harder.
Obviously you can't put together a test without being able to get repeatable measurements on primers and primer pocket depth and you can't get repeatable seating in pockets that aren't consistent. You also can't repeatably seat beyond bottomed if you can't measure that.
The Lapua brass I've worked with is fairly easy to feel a very noticeable "bottomed out" feel even before uniforming the pocket.
The Alpha brass is often hard to feel the "bottomed out" primer. It's better after uniforming but still not as consistent as the Lapua.
Once you can feel a definite bottom you can apply tension measurable in .001"s to set the preload, or tension or crush on the anvil. Many people are calling it crush but without being able to see and measure whats going on inside the pocket there is no way to know exactly how much actual anvil crush is obtained.
Using measurable tension is what it is but there is still the variance of the pocket. Ununiformed is a lot and I suspect even uniformed pockets have some but not nearly as much. There has to be a friction loss as well as tool deflection loss that keeps what you read on the indicator from being 100% linear to the movement of the primer.
The primers themselves are very hard to measure and have their share of inconsistencies. For thickness you can line up off the anvil to measure the cup or measure on the anvil to obtain overall thickness but you can see with the naked eye anvil protrusion varies from primer to primer.
Nobody including me wants to sort primers dimensionally so that puts it back to applying a measurable amount of tension on a bottomed out primer to increase the odds of getting them more consistent than just bottoming them out and giving them an extra squeeze.
Setting primers to .003" below flush means nothing if the pockets aren't uniform and there is variance in the primers themselves. Many times we think what we're doing is repeatable when it's not.
Like I said up top I'm curious to hear thoughts from the thinkers 😁 here.
Couple of clarification points:
-Think you meant to say "primer inconsistency "
- their are also prominent shooters such as Cortina, who think the that uniforming primers causes more inconsistencies than it eliminates.
For the last 4 years I have always uniformed pockets but plan to test Cortina's statement.
Quote from Dave: "There are a few new tools out that claim to be able to seat a primer to an exact depth and apply a measurable amount of crush or preload." Important to point out here that these tool makers are claiming exact depth based on feeling the "bottom out" or by calculating the difference between cup depth and primer height. It's interesting to note that those same tool makers don't agree on how to mechanically acquire their goal.
I have no doubt that good and especially consistent ignition can be affected by the varying length of firing pin fall and also the varying amount of primer crush. Interestingly these two focal points, in certain circumstances, can be opposed to each other. If you have a short primer in a deep pocket, a 3 thou crush could produce a 7 thou below flush seating. Reversing the primer and the pocket extremes, the same 3 thou crush could produce only a 2 thou below flush seating. Between those two extremes there is a 5 thou difference in firing pin fall.
For the best in precision, I think you need to know the range of both your primer height and pocket depth. From that point you can sort to your own desired limitations. Somewhere in there, I would expect subtle changes that can not be picked up on target.
Quote from Jerry,
their are also prominent shooters such as Cortina, who think the that uniforming primers causes more inconsistencies than it eliminates.
Yes there are, what I'm saying is if your goal is consistent measurable seating without having to somehow take into account tool deflection and varying primer yield and distortion from inconsistent pocket depth tapered hole diameter i have to disagree.
I could very well be wrong about tool deflection also it could be 100% primer yield and distortion when the simple math of the pocket depth, primer thickness and the measured stroke of the tool and below flush measurements don't add up.
Agreed
I like this guys videos.. he just did one on this topic dave.. watch it and you can make up your own mind whether its helpful or not..
https://youtu.be/Ep4KOhCWsV0
I've seen that video before and many others.
Towards the end he says seating to an exact crush is more difficult than it sounds and he needed a better tool to do it accurately.
Similar to what I'm saying.
Tests that use velocities as results are telling half the tale and not the important half in my opinion.
With the right tools I can set a primer to bottomed + whatever tension I desire.
I can go ahead and call it crush but I question whether the cup is crushing or the anvil as intended.
We can only test what we can accurately apply & measure repeatedly.
My OP wasn't questioning the validity of seating a primer to a measurable depth. I'm asking if anyone else here is experimenting along these lines and what they've found.
I shoot with an individual that likes everything exact. So he invested in some tooling so that he could set his primers to the exact depth he wanted....say 0.003 below the base. When he started shooting, he was getting a high % of failed to fire cases. He checked his head space, his firing pin depth and spring rate etc. His final conclusion was that he needed to bottom out the primer against the bottom of the pocket. So after doing so, his FTF went away. Can't speak to how good his shooting was or wasn't due to the primer seating but at least they did fire.
OK I think I've confused everyone and probably myself.
The below flush is kind of a sorting tool for me.
I'm bottoming them out into a uniformed pocket that I know is .123" deep along the walls.
Uniforming to that depth also takes the high or low spot out of the center of the pocket so it's nice and flat.
So I bottom them out and add .0035" tension or crush to the primer. Then I sort them for below flush. Knowing the pocket depth is uniform any variance is in the primer itself.
In the pic the cases left front tray are .003 BF front right are .004 BF
Rear tray left side is one .002 BF and right is .005 BF
The 3 outliers will be foulers the 42 cases within .002" will be sighters and records.
This in my mind makes them as close to the same as possible from a standpoint of pin fall into a solid seated primer.
.003 BF is a meaningless measurement if they are not bottomed into a uniform pocket.
(https://i.ibb.co/vPT6jsd/IMG-20220531-201445105.jpg) (https://ibb.co/vPT6jsd)
Thanks Dave....your last post made sense. Have you taken and shot groups from a mix of primer depths to verify that all this effort makes a difference?
Quote from: autoxforfun on May 31, 2022, 08:36:03 PMThanks Dave....your last post made sense. Have you taken and shot groups from a mix of primer depths to verify that all this effort makes a difference?
I haven't had time yet. I have shot 4 matches now with them sorted like this and in spite of mostly bad to horrible conditions and minimal tuning I feel I've done well with them and I'm learning how to get the spread on the BF tighter as I go.
The BF isn't really the depth in my mind. The depth is the bottom + the crush. On a uniformed pocket the BF becomes the the measuring stick of how consistent the primers themselves are.
So far it's the best way I've figured out how to have a consistent crush.
I think folks might be getting confused in this thread because they are thinking about measured primer seating depth based on a measurement of how far below flush the primer top sits below flush with the case head.
Go back and read the OP and my response with points of clarification. Measurement of exact seating depth is at the base of the primer and the bottom of the primer cup.
The tools Dave is referring to is the Primal Rights primer seater and the platform manufactured by F-Class Products that is produced to use the PR seater with a dial indicator. Dave and I have been working with these tools recently. I was able to get both of these tools a few months before Dave got his and I started working with them immediately. That work got interrupted by some health problems and Dave has now done more with them than I've been able to do.
The purpose/question Dave initially posted is: have any of you also started looking at the precision affects of primer seating with a known/measured amount of primer/anvil crush or preload as Dave likes to call it.
Correct /\ 😁
Here's once fired Lapua 6 BR
The PR gage shows .123" on a brushed out pocket.
The A1 digital with the different tip shows only .120"
The PR is measuring the center of the pocket.
The A1 is measuring the perimeter where the primer cup actually seats.
After uniforming it measures same on PR but .122" on the A1 so now my primers have a uniform bottom to base seating off of.
(https://i.ibb.co/gDfYGQ7/IMG-20220601-165250471.jpg) (https://ibb.co/gDfYGQ7)
(https://i.ibb.co/s61GVkX/IMG-20220601-165258290.jpg) (https://ibb.co/s61GVkX)
(https://i.ibb.co/2KxDdJz/IMG-20220601-165326387.jpg) (https://ibb.co/2KxDdJz)
Guys the difference in the indicator tips is the tip on the PR tool is a small diameter flat face where the A1 indicator comes with two tips, one a small diameter flat face and the other a larger diameter concaved face.
The small diameter flat face works great for measuring a seated primer for BF but when measuring pocket depth the larger diameter concave faced tip actually measures the perimeter of the bottom of the pocket where the primer is actually bottoming and the anvil itself starts to crush.
Dave mine are packed away. If it's not too much trouble for you, could you check the diameter difference with a micrometer if you have it?
.1455" on the flat face PR tip
.1685" on the concave A1
SR pocket is .171" inner bottom diameter
(https://i.ibb.co/vc7T2yf/IMG-20220601-191939617.jpg) (https://ibb.co/vc7T2yf)
(https://i.ibb.co/pPChcxs/IMG-20220601-191948977.jpg) (https://ibb.co/pPChcxs)
Jerry and Dave, just when I was getting happy with where I was in this rabbit hole you guys have to come along and try and pull me deeper...lol. But we're all about shooting those small groups.
Quote from: autoxforfun on June 01, 2022, 10:57:47 PMJerry and Dave, just when I was getting happy with where I was in this rabbit hole you guys have to come along and try and pull me deeper...lol. But we're all about shooting those small groups.
What I think the benefit will be is a reduction in some of those unexplained groups that "got away" for instance when you sit down to shoot two targets side by side like in a 600 yard IBS match where the first target is shot then a second sighter period and the second is shot.
When one group is noticeably larger, has a flier or is shaped noticeably different and no condition change was noticed and there's really no explanation for the difference.
Any improvement in individual group size may will likely be measured over the course of the season in a 10 or more target agg. At 600 yards possibly more high 1s and low 2s vs low 2s and high 2s with the occasional 1
Look at all the steps some of us take to "make them all the same"
Weight sorting components
Dimensional sorting components
Weighing powder to the kernel
Brass prep steps
Bullet seating depth to .0005" +/-
Etc.
Then we get to this step of priming brass and pushing a primer into an inconsistent hole by feel is good enough?
People claim to get this consistent light crush by feel on a hand tool. Mmmm OK
Groups and aggs get smaller and records fall. Probably not by people who are happy with where they are at and not looking for the next stone unturned.
Quote from: HufD63 on June 02, 2022, 06:18:11 AMQuote from: autoxforfun on June 01, 2022, 10:57:47 PMJerry and Dave, just when I was getting happy with where I was in this rabbit hole you guys have to come along and try and pull me deeper...lol. But we're all about shooting those small groups.
What I think the benefit will be is a reduction in some of those unexplained groups that "got away" for instance when you sit down to shoot two targets side by side like in a 600 yard IBS match where the first target is shot then a second sighter period and the second is shot.
When one group is noticeably larger, has a flier or is shaped noticeably different and no condition change was noticed and there's really no explanation for the difference.
Any improvement in individual group size may will likely be measured over the course of the season in a 10 or more target agg. At 600 yards possibly more high 1s and low 2s vs low 2s and high 2s with the occasional 1
Look at all the steps some of us take to "make them all the same"
Weight sorting components
Dimensional sorting components
Weighing powder to the kernel
Brass prep steps
Bullet seating depth to .0005" +/-
Etc.
Then we get to this step of priming brass and pushing a primer into an inconsistent hole by feel is good enough?
People claim to get this consistent light crush by feel on a hand tool. Mmmm OK
Groups and aggs get smaller and records fall. Probably not by people who are happy with where they are at and not looking for the next stone unturned.
What makes this forum so valuable and continues to do so, are the contributions from you, Jerry and others regarding the finer elements of precision loading/shooting. Thank you for putting the details out there so we can all benefit....very much appreciated. So even though I may be comfortable now, that usually doesn't last very long and then I'm looking for the next knob to turn to make it better or faster.
I have thought for awhile now, that sorting primers may be something to try and evaluate. Seating depth/pocket forming is now on the list.
"Groups and aggs get smaller and records fall. Probably not by people who are happy with where they are at and not looking for the next stone unturned"
AMEN!
The will to win can only be fulfilled by your willingness to prepare.
I went back and read thru this thread a couple times and followed up on the companies providing the tools. A lot of good information here. I want to thank Dave for starting the topic and all those that contributed.
Quote from: autoxforfun on June 05, 2022, 12:29:23 PMI went back and read thru this thread a couple times and followed up on the companies providing the tools. A lot of good information here. I want to thank Dave for starting the topic and all those that contributed.
I've seated about 700+ rounds of brass in the last week getting ready for the 2 match weekend in MN then onto the Rendevouz in MO.
I've probably seated 1100+ on it now and at first was frustrated that while it may or may not have been doing what it claimed I could not accurately measure it. Jerry and I have had many conversations on how to get the most out of the tools and I can say from my experience the key to being able to get a consistent measurement you can trust is uniforming with a precision uniformer that the depth can be controlled on. The consistent feel of the bottoming of the primer in the pocket let's you accurately set the crush.
I feel to get a consistent below flush seat the pocket needs to be in the .1215" to .123" range. If the cutter could consistently cut .122 - .123 it is about perfect.
Many uniformers won't cut this deep. One of the adjustable I'm using went too deep on the shallowest setting so I was filing the blunt end of the carbide cutter to get it deeper in the holder to get the cut in that range.
Some cutters are larger diameter than others and after discussing it with Jerry more than once his 21st Century tool is .170" in diameter and cuts minimal if any sidewall which is ideal.
I've heard the PMA tool is designed for Lapua brass to NOT cut sidewall only depth.
This would be beneficial to pocket life IMO.
Most tools will easily get to .001" variance in depth and even closer to .0005" with the occasional one getting to a full .001" variance.
It's all achievable and repeatable with the right tools. The downside is those tools are not cheap LOL but the press is so much nicer to use than a handheld so even if I can never prove this all matters on paper I'll continue to use it for ease of function and the ability to sort based on a measurable known vs a feeling.
I kind of actually enjoy priming with this set up vs the handhelds.
I talked to Shawn Williams at North Ridge Rifles about 6 months ago and asked him why he was using the Primal Rights seater. I expected him to say "for the added precision". His first answer was, "because it's saving my hands and wrists". Precision was his second reason.
After using this procedure awhile I think the next time I uniform a set of pockets .121" would be my target depth on the pockets.
With .003" crush I'm getting a few @ .006" below flush. I don't really know that it matters but it seem the less you take out of the pocket the better for longevity.
Guys,
OK, some of you have the fancier tools (e.g Primal Rights CPS) for primer seating. In theory, once you've set your depth, or crush, then you're good to go, because in theory you can't "over crush", because the ram bottoms out.
The question: Is anyone actually measuring all your primed cases for the amount below flush, and what variance are you seeing due to possible differences in the case rim thickness?
I'm still out here sitting on the fence regarding additional tools, primer gauges etc, though I think I might be swayed to the CPS due to the "saving my hands and wrists" (Thanks
@jvw2008)
Quote from: VA-XBolt on July 12, 2022, 11:30:26 AMGuys,
OK, some of you have the fancier tools (e.g Primal Rights CPS) for primer seating. In theory, once you've set your depth, or crush, then you're good to go, because in theory you can't "over crush", because the ram bottoms out.
The question: Is anyone actually measuring all your primed cases for the amount below flush, and what variance are you seeing due to possible differences in the case rim thickness?
I'm still out here sitting on the fence regarding additional tools, primer gauges etc, though I think I might be swayed to the CPS due to the "saving my hands and wrists" (Thanks @jvw2008)
I'm not using the depth stop. I'm feeling the bottom then applying an exact amount of crush measured by dial indicator on the f class products stand.
My experience has shown me no matter how uniform the pocket .003" crush does not give the same below flush measurement across a set of brass.
Some of the variation is likely in the rims as you said but I believe some lies in the varying friction in a pocket.
I've determined for my use the most practical method is uniformed pockets with primer seated as above. The cases are sorted for below flush and will vary from .001" to as high as .003" whichever group has the most cases becomes my record rounds. The next largest group which has always been within .001" of these one way or the other become my sighters then the outliers are foulers.
With the dial you can tell crush would not be even with the depth stop because the dial reads different depths when you fell bottom. This would have a lot to do with cup thickness and anvil protrusion.
I'm not saying another method would not work but the way I'm doing it I'm satisfied I'm getting consistent crush because I can actually measure it.
Consistent below flush should make for consistent ignition.
Different crush will optimize ignition and it can be seen on target just like a powder or seating ladder.
If a guy were really gonna go off the deep end sorting primers by cup height would take a little more +/- out of the equation but at the moment I'm happy with where I'm at.
Both is optimal. 😊
Jerry will be turning case heads to uniform the extractor groove before long 🤣
Quote from: HufD63 on July 12, 2022, 12:26:32 PMI'm feeling the bottom then applying an exact amount of crush measured by dial indicator on the f class products stand.
OK, that makes sense. And yet another tool I didn't know existed. I do like the idea of the F Class stand, if noting else, so that I can easily move the CPS around on my bench. The addition of the crush indicator is a bonus.
Quote from: HufD63 on July 12, 2022, 01:02:40 PMJerry will be turning case heads to uniform the extractor groove before long 🤣
As long as that doesn't turn into yet another tool I need to buy... LOL
Hmmm I might need to get a mini lathe after all. Chuck up a le wilson shell holder backwards and feed the cases one at a time into the cutter.
Naw. Just need to talk to Mr Blake about an accessory for the autoDOD.
Quote from: jvw2008 on July 12, 2022, 08:01:12 PMHmmm I might need to get a mini lathe after all.
Please NO MORE TOOLS.. My bench is already overrun!
I habe always seated with a press, it is easy to over do it and sink them in a measurable amountbdeeper.
Once I added an extension to the press handle and put an indicator pinon the end of it. That press was mounted parallel to the wall. If you brought the indicator to the same spot on the wall and measured the primer depth, you could become very repeatable as far as "crush" goes! With no long range to test results a test should be able to conduct with simple chrono results.
I always measured case head to primer cup. Adding 2 to 4 thou of crush is easy in a press. Consistency by "feel" is harder to accomplish.
I'm not a benchrest shooter but I have always used the standard rule, listed in all of the manuals that I have, along with more than a couple writers in Handloading magazine. I seat all of my primers to .001 to .002 below the case head. I have not had any problems once I got this method down.
Not to say any of you are mistaken, just how I learned to seat primers. I had a couple primers fail to ignite way back when I started reloading but not since then.
My suggestion is find the process that suits you and stay with it.
[quote author=missippyman link=msg=143005 dat
I'm not a benchrest shooter but I have always used the standard rule, listed in all of the manuals that I have, along with more than a couple writers in Handloading magazine. I seat all of my primers to .001 to .002 below the case head. I have not had any problems once I got this method down.
Not to say any of you are mistaken, just how I learned to seat primers. I had a couple primers fail to ignite way back when I started reloading but not since then.
My suggestion is find the process that suits you and stay with it.
[/quote]
I certainly won't argue with the last sentence of your post. Seating to .001 to .002 below the case head is basically a "good enough" measurement and it's obviously making them go bang.
I realize what I'm doing is not for everybody and I'm not trying to to get anybody to throw down the money on the tools to measure primer crush just sharing what I've learned.
The whole process is not about making the gun go bang reliably it's about wringing consistently smaller groups out of a gun by optimizing the ignition timing.
To adequately test a difference in crush a load must be tuned as good as you can get it. Powder, seating, neck tension and primer preference. Before I had a chance to test it on paper at 600 yards I was crushing .0035" after winning the 2022 Long Range Rendevouz in June with a small amount of that lot of bullets i put together a test of 3 shot groups at .002" - .006" which revealed .003" shot smallest and not just by a little. .002 & .004 were good and .005 & .006 were starting to open up.
Proof enough for me it matters for benchrest accuracy. I'll add the picture in a few minutes from my phone
Like I said I was crushing between 3 & 4 thou at the Rendevouz sure wish it had been 3 LOL
(https://i.ibb.co/jfttPxF/IMG-20220728-212203.jpg) (https://ibb.co/xLZZtcQ)
Those are the same brass bullets and powder used at the Rendevouz, same charge weight, same seating depth. Shot at 600 yards. Only difference is primer crush.
Interesting to note also the smallest group has the largest SD / ES and the largest group has the smallest.
Chasing single digit chrono numbers ican be a waste of components and barrels. The target tells the truth.
All measuring below flush measures is below flush!
If you accurately measure primer pocket depth then accurately measure a primer cup then seat the primer then you can measure below flush and do the math and figure crush or lack thereof.
Man those results are actually insane.
I need a different method of doing my primers I guess.
Quote from: LeadHammer on July 28, 2022, 10:18:48 PMMan those results are actually insane.
I need a different method of doing my primers I guess.
While it is only one test I like how it goes from small to smallest then back to small then it scatters then groups up bigger.
Typical "node" behavior that actually lends legitimacy to the test in my opinion.
Quote from: HufD63 on July 28, 2022, 10:36:48 PMQuote from: LeadHammer on July 28, 2022, 10:18:48 PMMan those results are actually insane.
I need a different method of doing my primers I guess.
While it is only one test I like how it goes from small to smallest then back to small then it scatters then groups up bigger.
Typical "node" behavior that actually lends legitimacy to the test in my opinion.
Very interesting data for sure. Looking forward to more tests.
Quote from: HufD63 on July 10, 2022, 01:12:09 PMAfter using this procedure awhile I think the next time I uniform a set of pockets .121" would be my target depth on the pockets.
With .003" crush I'm getting a few @ .006" below flush. I don't really know that it matters but it seem the less you take out of the pocket the better for longevity.
I want to update this statement a little. I kept my original .122-.123 depth cut the same because I realized the variance in below flush was in the primer itself or rim thickness variance. I could sort primers by thickness as well as identify these cases that keep coming up with a bigger below flush and match them to thicker primers :o but no I'm not doing all that LOL this is working IMO
This is however on Lapua brass with CCI 400s on my Alphas with BR4s the same depth is getting most primers with a .002-.003 BF with a few at .001-.002 and a very few outliers at flush to .001 above flush. With the same pocket depth this is likely the thicker cup on the BR4 compared to a 400
I was thinking about going a thou deeper on the alpha case but decided against it because if I wanted to run a different primer with a thinner cup I could end up with an even deeper BF
So for now I'm sticking to the original .122-.123 uniformed depth.
The Centurty 21 uniforming tool is by far the best I tried but I've heard the PMA tool for Lapua brass is as good or better at uniforming depth without cutting sidewall.
6mm BRA and 6mm Dasher Alpha/Lapua Brass:
For Alpha I use the 21st at 0.122 which is simply a skim of the bottom of the pocket. As Dave just reported, there is less pocket variance in the Alpha. This uniformity is consistent with Alpha across the board. IMO it is simply the highest precision made brass I have found.
Many top shooters today (mainly F Class) such as Eric Cortina, recommend leaving primer pockets alone - ie. don't uniform. Based on my dimension measurements of multiple brass offerings I don't agree with his advice. Eric doesn't use Alpha, he uses Lapua. Personally, if there was any brass out there that I would consider not uniforming pockets it would only be Alpha.
Lapua is, comparatively, still extremely good and in some areas possibly better than Alpha's offering. If Lapua had Alpha consistency I would lean towards the Laupa just for its slightly larger case capacity.
Early on in production Alpha unfortunately had some batches of brass that didn't hold primer pocket size well with multiple firings. True to their commitment, the company went back and did a reformulation of their brass composition and have now labeled it OCD brass. If anything they may have over corrected for hardness since most of us find the Aplha pockets are more difficult to cut with a uniforming tool. At this point in my use of the Alpha OCD brass, I could not say how long these pockets will hold up, but I'm pretty sure it will be just as long as the Lapua pockets.
I have some of that first run Dasher brass. It was extremely consistent and I was tickled eliminating hydroformed brass. On second firing, primers would fall out. I called Alpha and they told me they messed up and had the new OCD developed. I still have the 500 pieces of a boat anchor--just can't make myself throw them away. I still shoot Alpha in Dasher and 6GT.
My first batch from them was BRA brass. I had heard of a possible soft primer pocket problem so I did an initial firing with a light load to harden the bases a little. I may have had an odd batch, but after the initial firing I cycled that brass 6 more times without problems.
With the OCD variety, I have no hesitation to go to a full load and compete with the virgin brass. Last month's match win was virgin brass for me. Not having to fireform the Lapua and going directly to the virgin Alpha brass for competition has saved me a very significant amount of reloading components. Previously I have tried the virgin Lapua, fireforming it in a match - not a good move.
No question about it - I'm an Alpha fanboy.
For me lapua would be my 3rd choice in brass.. alpha and peterson is a toss up in my opinion. Both are top shelf..
Quote from: gman47564 on July 29, 2022, 05:13:05 PMFor me lapua would be my 3rd choice in brass.. alpha and peterson is a toss up in my opinion. Both are top shelf..
+1 from me for Alpha and Peterson
I hardly ever see Alpha around here, do see Peterson however.
Quote from: gman47564 on July 29, 2022, 05:13:05 PMFor me lapua would be my 3rd choice in brass.. alpha and peterson is a toss up in my opinion. Both are top shelf..
No Peterson experience to speak from, my Alpha brass has less capacity than my Lapua. It is quicker to pressure up and get bolt lift, if there is any humidity better make sure I keep a chamber mop handy and use it frequently. The brass is just grabby for lack of a better word.
I've heard Peterson has similar capacity as Alpha.
I think the next time I need brass for a 6 BRA I'll go back to Lapua in spite of the fireforming.
The only reason i say lapua would be my 3rd choice is because i think peterson and alpha is a little easier to work with and i get better sizing results with it.. its a touch softer than lapua i believe.. dont get me wrong.. lapua is really good brass also and i use it in 3 or 4 carts..
I just picked up a box of lapua 6.5 prc brass to try and im excited to see what i can come up with for a load compared to my old hornady brass..
Definitely agree with the early pressure up on Alpha versa Lapua. I've seen the same with the smaller capacity Peterson brass when compared to other brands. It's not a big problem unless you are in a match and you start getting a bolt lift hard enough to disrupt the rifle in the bags. Then it's a disaster. As I said earlier, I run virgin Alpha brass in matches at 3010 - 3020 fps with a 103 gr bullet using the same powder that Dave and many others use - but I am not experiencing a hard bolt lift and can run my rounds smoothly. As a disclaimer, I will say I had one batch of BRA brass last year that was initially just a tiny bit sticky with a stiffer bolt lift than I would tolerate long term. The issue went away on second firing.
That Dasher velocity node I listed above is up there but the charge required to get there with Alpha brass is about one full grain less powder than a typical Lapua case would require for the same chamber pressure (as it relates to MV). So less powder for equal velocity using Aplha. Still though the small case volume pressures quickly.
Dave's issue with a sticky bolt lift on first firing and sometimes even second firing is not unique to just him. I've heard the complaint from several other competitors. But I've also talked to other Alpha users who, like me, are not experiencing this issue. So why does Dave have a sticky bolt problem with Alpha and I don't. I would like to know the correct answer to that question. 😊 The thoughts I've had involve: environment humidity difference, difference is lots of brass, difference in actions during cycling a round, difference in brass prep, difference in chamber cleaning, different neck tension/grip, difference in BRA verses Dasher case shape ...... the list goes on and I still don't know.
Like you it was a real problem on the virgin cycle. It got better with a switch from 400s to br4s. There was still some that could be "fixed" with the chamber mop.
Using the chamber mop has become a habit because of this and the bolt lift is almost non existent now. I'm going to say it was/is an atmospheric condition that is related to high humidity.
I wonder if it's not due to the stronger nature of the brass having a different alloy make up.
It could possibly be cured with a sizing die or reamer tweak but one could by a lot of Lapua brass with the money it would take to go down that road.
😂 you are right, however on the other side, you could spend a lot of time and cull expense sorting the Lapua to the consistency of the Alpha.
This discussion is interesting in that it shows how different approaches can be used successfully to push for the pinnacle of precision. It's not a matter of the right way or the wrong way - it's a matter of the way that works best for you.
The Peterson brass, has anyone had sticky virgin case firings?
Yes - in my 300 Norma Mag. Went away on second firing. Love the Peterson brass for that rifle. Better than Lapua and Norma brass for me.
Quote from: LeadHammer on July 30, 2022, 09:48:56 AMThe Peterson brass, has anyone had sticky virgin case firings?
I haven't in 25 creedmoor, 284 winchester, 280ai or 6br..
I'm pushing a 230 gr bullet at 2960. 😊
Push it hard enough any virgin brass will over pressure.
Lol.. thats not the cases fault then jerry.. :D
Quote from: gman47564 on July 30, 2022, 11:55:53 AMLol.. thats not the cases fault then jerry.. :D
If a different brand brass will push it to the same speed on a virgin case without lift it is a characteristic of the brass not necessarily a fault.
If a guy can get virgin brass to perform where it shoots smallest on the first firing the time and expense saved from fire forming is staggering.
This is where I'm coming from considering going back to Lapua in spite of needing fire formed.
I was shooting 2x fired Lapua batch of 300 at The Rendevouz including the ff load.
Those 300 cases were ff breaking in 4 new barrels so it helped get them a little further along to a more stable place.
I have not been pushing my 6.5 at all so likely would not see the sticky virgin brass.
The only Peterson brass that I've had that would stick was with my 6.5-284. Never had an issue with Alpha or Peterson in 6.5CM or Dasher. I've also run the Norma 6.5CM and Dasher brass and have been pleased with the results. The primer pockets just don't seem to hold up as long as the others is my only observation.
Quote from: autoxforfun on July 30, 2022, 06:42:10 PMThe only Peterson brass that I've had that would stick was with my 6.5-284. Never had an issue with Alpha or Peterson in 6.5CM or Dasher. I've also run the Norma 6.5CM and Dasher brass and have been pleased with the results. The primer pockets just don't seem to hold up as long as the others is my only observation.
Interesting, so many variables with each brand.
Bumping this to recommend the PMA Lapua brass primer pocket uniformer.
Through the process in this thread I struggled to find a uniformer that would cut only the bottom of the tight Alpha pockets once you start cutting sidewall it's a bear to hang onto and tough on the hands.
For anyone that's never tried it I'll just say you'll invent some new swear words and phrases LOL
https://www.pmatool.com/pma-lapua-small-primer-pocket-ultimate-uniformer-complete-w-handle-and-power-adapter/
Works as advertised removing the brass in the pocket bottom and disturbs as little of the sidewall as any I've used.
The larger face seemed to NOT scuff up the heads of my cases like other tools did as well.
No regrets here for me, I have a collection of other tools that will gather dust.
I do wish they had made it depth adjustable like the 21st Century one. Can you mic the diameter of the cutting tip on your PMA and the 21st?
Quote from: jvw2008 on January 24, 2023, 11:34:13 AMI do wish they had made it depth adjustable like the 21st Century one. Can you mic the diameter of the cutting tip on your PMA and the 21st?
Yes this evening, it cuts a thou or two deeper than I thought I'd like .124" with a few running over to .125" but with seating 400s with .003 crush the bulk of the 27 cases I'm testing seated .002" below flush 70-80% I'd say with the remainder.001" or .003 BF
That's without getting crazy and sorting primers to thickness so I can't complain about that consistency or the pocket being too deep.
You have your rim variation in there as well. Theoretically you detour around that by feeling the crush but as I've said before, I'm fooling myself to believe I can tell a difference of one thou simply by feel.
I've convinced myself of that by using the CPS and FCLASS dial indicator platform.
Rim thickness is beyond my ability to accurately measure and if I could accurately measure it I can't believe I could uniform it to better without a good chance of screwing up the case head.
Therefore I've put those notions into the beyond my control dumpster.
Maybe the tool that Bullet Jockey mentioned will be out soon.
Not easy to measure because of the cutter points but the PMA consistently came up at .170"
The 21st Century at .171"
Amazing the difference a thou makes
(https://i.postimg.cc/Njmpb7FV/IMG-20230124-182251307.jpg) (https://postimages.org/)
(https://i.postimg.cc/j2B44Lbt/IMG-20230124-182310016.jpg) (https://postimages.org/)
K & M pushing close to .172"
RCBS close to .173"
Sinclair about .1706"
So I would say if anybody won't spring for the PMA tool the Sinclair is your next best bet but I do remember it being difficult to use also.
Thanx Dave. I can believe it's just a thou difference.
Quote from: jvw2008 on January 24, 2023, 06:44:17 PMThanx Dave. I can believe it's just a thou difference.
I can believe it's just a thou difference!
I can't believe a thou makes that much difference!
Are you using the PMA one chucked to a drill or screwed to a brass prep machine?
Can you see any difference in the cutting blades? Different angle?
Quote from: jvw2008 on January 24, 2023, 08:18:44 PMAre you using the PMA one chucked to a drill or screwed to a brass prep machine?
Dewalt hex head impact driver.
Quote from: jvw2008 on January 24, 2023, 08:28:21 PMCan you see any difference in the cutting blades? Different angle?
They look similar.
Had a PM about this process this morning so instead of hunting for it every time I get a question I've stickied it.
I'm still using the procedure and tools detailed in this thread and remain convinced it's improved priming process and overall competition results.
The F Class stand and indicator bring the portable ease of use and the ability to measure your work.
I'm convinced more than ever for the tool to do what's advertised you can't use it as advertised and uniforming pockets to an exact depth is critical to consistent pin fall and lock time contributing to ignition timing.
I've got about 10 different uniforming tool and for the depth adjustability and smaller diameter cutter than most of the other I recommend the 21st Century tool.
The PMA tool marketed for Lapua brass is slightly less diameter and would be better than the 21st except there's no depth adjustment and the cutter I received cuts .003" deeper than I want.
My K & M is adjustable and does fine as well as a cheap RCBS.
Alpha brass with factory tight pockets absolutely needs uniformed and is very difficult to do with any tool I've used.
This tool placed on the case web area will allow you to hold and control your uniforming with any manufacturer's case.
(https://i.postimg.cc/Yq65jjJD/IMG-0799.jpg) (https://postimages.org/)
(https://i.postimg.cc/qR6Yr7sL/IMG-0797.jpg) (https://postimages.org/)
This tool can be a stinker to find so here is a link:
https://www.brownells.com/reloading/case-cleaning-prep/case-neck-turning/neck-turning-handles/
Pretty sure I have one in a box of old neck turning gear.
Quote from: HufD63 on June 08, 2023, 08:02:01 PMPretty sure I have one in a box of old neck turning gear.
Think I showed it to you a few years back. Shawn was the one who initially told me about it.
Wasn't sure where to put this little post but without this equipment there would be no post so here it is.
Getting another 100 new 6 BR Norma ready to go for the TL3
New blue box Lapua at least 5 years old but probably 7-8, 101 pieces of brass. I ran them through a .2415" mandrel to smooth out a few shipping dings and give them som consistency.
I've been not uniforming brass on the first firing lately for no reason other than to see how consistent the pockets are. I'm skipping the measuring the original depth part because I just want to feel how they seat, give them a .003" crush and measure the below flush on the primer.
101 pieces total
11 pieces <.003 >.002"
84 pieces between .003" & .004"
6 pieces >.004" <.005"
Primers seated firm with a predictable stop making it easy to read off another .003"
Wish I knew where another 9 boxes of this lot were 😂
(https://i.postimg.cc/RVWB0VMy/IMG-20230706-193518436.jpg) (https://postimg.cc/8jg3KGfm)
It's Lapua - good stuff! But yes that is pretty consistent.
Those CCI's sure seem to be the most forgiving on crush from what I've seen.
Quote from: Bullet Jockey on July 07, 2023, 09:59:18 AMThose CCI's sure seem to be the most forgiving on crush from what I've seen.
I haven't used much of anything else other than some 205m & 210m federals but I'd have to agree with you.
I only use Fed primers for rifle, but use CCI for pistol. Federal squish ultra easy in comparison.
Stumbled upon this....
https://youtu.be/5Tthv2Rb810
My mind is NOT changed. While I have a great amount of respect for this gentleman I do disagree with his testing methods on things.
Before anyone gets their panties in a knot I think far too many people put WAY too much credit into SD / ES for testing things. The only thing ES & SD should be the judge of is techniques to lower ES & SD The paper is the ultimate judge when trying to see if something makes a difference to accuracy or precision.
I would also not rely on a shotmarker especially with that big of sample and an aimpoint that offers a chance for error as he experienced.
I would also not conduct a test to see if something makes a difference in a mirage.
A test with that many samples in an already less than perfect condition only adds to more unknown condition variables not to mention the combination of ambient temperature and barrel heat pushing the load out of the node.
The more I watch a test like this the more I'm convinced there's nothing better than a ladder of 4-5 sets of 3 with colored bullets shot to the same aimpoint NOT round robin so you can see exactly what those 3 did in comparison to the other sets of 3.
I would still be interested in the tool that takes the rim thickness out of the equation and testing with it.
That would be a better test IMO, does varying rim thickness matter?
I'm satisfied that in a uniformed pocket with a .003" crush I'm getting more consistent accuracy than what I was doing previously.
Weight sorted but NOT measured for height primers will give me a box of 45 seated to +.003" that I can get 35-40+ with a below flush variance of <.0015"
I'm not sure the weight sorting adds any accuracy to the mix but as I've said before I'm doing that to find any horrific outliers.
Prime example of a singular focus on one variable while ignoring the others. A simple lack of case capacity consistency could white wash primer affects on velocity and precision. Science and research are great only when done properly. This is similar to "crap in gives crap out" with software.
Any of the multiple things he acknowledged in the video makes the test inconclusive in my opinion.
Like I said great respect for the man who is very knowledgeable but I'm not buying his conclusion.
Edit... After rethinking what he was testing I am buying his conclusion. 😂🤣😂
Quote from: HufD63 on July 18, 2023, 04:11:51 PMStumbled upon this....
https://youtu.be/5Tthv2Rb810
My mind is NOT changed. While I have a great amount of respect for this gentleman I do disagree with his testing methods on things.
Before anyone gets their panties in a knot I think far too many people put WAY too much credit into SD / ES for testing things. The only thing ES & SD should be the judge of is techniques to lower ES & SD The paper is the ultimate judge when trying to see if something makes a difference to accuracy or precision.
I would also not rely on a shotmarker especially with that big of sample and an aimpoint that offers a chance for error as he experienced.
I would also not conduct a test to see if something makes a difference in a mirage.
A test with that many samples in an already less than perfect condition only adds to more unknown condition variables not to mention the combination of ambient temperature and barrel heat pushing the load out of the node.
The more I watch a test like this the more I'm convinced there's nothing better than a ladder of 4-5 sets of 3 with colored bullets shot to the same aimpoint NOT round robin so you can see exactly what those 3 did in comparison to the other sets of 3.
I would still be interested in the tool that takes the rim thickness out of the equation and testing with it.
That would be a better test IMO, does varying rim thickness matter?
I'm satisfied that in a uniformed pocket with a .003" crush I'm getting more consistent accuracy than what I was doing previously.
Weight sorted but NOT measured for height primers will give me a box of 45 seated to +.003" that I can get 35-40+ with a below flush variance of <.0015"
I'm not sure the weight sorting adds any accuracy to the mix but as I've said before I'm doing that to find any horrific outliers.
Keith was my teammate and wind coach for about 6-7yrs.....I didn't always agree with his findings nor his delivery methods on certain subjects.......His primer seating tool is/was legit, he had some sort of deal with 21st Century to bring it to market not sure if that has fell through or not.
Quote from: jvw2008 on July 18, 2023, 04:35:23 PMPrime example of a singular focus on one variable while ignoring the others. A simple lack of case capacity consistency could white wash primer affects on velocity and precision. Science and research are great only when done properly. This is similar to "crap in gives crap out" with software.
Keith actually tested that as well....didn't make a hill of beans at 1k for Fclass. One of the guys on the team come up with a way to measure internal case capacity plus he tested Bison Armory case volume gauge.
Again BR isn't Fclass so it might be something that shows up in the aggregate I would think???
Large sample sizes are great for sorting bullets, case, primers, etc etc sorting 100 of 1000 only tells you what the 100 are like.
A shooting test is another story, I don't care who you are the more rounds into a group the bigger it gets for multiple reasons other than the obvious.
Testing in less than favorable conditions is great if you can spot a difference. If you can't there's no way to know if it was what you were testing or the condition.
Those were my two problems with his test.
Lastly if you believe as I do that it's the amount of crush that must be tested to see the improvement then the test did nothing in regards to that.
He seated a specific crush of sorted primers against an intentionally not uniform group of primers to simulate a not consistent crush and even lack of crush on some and after thinking about what he was comparing I'm not surprised at his results and do not question his findings.
While I still believe seating primers uniformly is better than not the true gain in my experience for BR purposes is testing the amount of crush to find the sweet spot so you can repeatedly accurately seat there.
Well I had a nice long post all typed out and lost it. 🙄
I will sum it up by saying there is little question that capacity affects velocity and velocity affects bullet flight. If that affect is not seen on target then other factors are in play - such as barrel compensation if that's a reality. Ignition is one of the most important aspects of internal ballistic and it starts with proper primer function. If an effect on target can not be recognized with grossly varied primer positioning, I would propose that the affect is there but buried by other variables either not realized or controlled.
Quote from: HufD63 on July 18, 2023, 05:34:26 PMWhile I still believe seating primers uniformly is better than not the true gain in my experience for BR purposes is testing the amount of crush to find the sweet spot so you can repeatedly accurately seat there.
100% agree....I've tested it and my team mates have tested it many times with positive outcomes. Groups shrink and ES/SD's shrink. I've tested from hang fire to about .012 crush.
Quote from: jvw2008 on July 18, 2023, 06:18:37 PMI will sum it up by saying there is little question that capacity affects velocity and velocity affects bullet flight. If that affect is not seen on target then other factors are in play - such as barrel compensation if that's a reality.
How much velocity variation do you typically see with internal case capacity differences?
I'm a believer in positive compensation at the distance you are shooting....anything other than that it's hard to see for me personally.
I should bump this thread more often 😂 really makes people think if nothing else.
I'm here to learn and share when I can. Discussion makes us all better reloaders and shooters!
Especially if you stay open minded ;)
This is a topic that I have no first hand experience with....just my disclaimer...lol. I have watched a number of his videos and have found them all thought provoking. In this one, he didn't state all of the other factors that he controls during his reloading, such as bullet sorting, neck tension, case sorting etc, but since he is looking for some pretty small improvements, I think it would be fair to say that he has a pretty good process that gives him some consistent results.
What hit me immediately was that the first thing he did was weight sort the primers. Is there agreement here that weight sorting has a bigger impact than seating depth?
Quote from: autoxforfun on July 18, 2023, 07:35:27 PMWhat hit me immediately was that the first thing he did was weight sort the primers. Is there agreement here that weight sorting has a bigger impact than seating depth?
Not to my knowledge Bob, I think the only thing everyone agrees in regarding primers is put them in the hole, smooth side out 😂
My thoughts on this.. I know their not worth much.. in my mind trying to test primer seating depth outside in conditions at distance is futile.. theirs just too many variances at play to honestly say yep this is the perfect primer seating depth.. to me the only real way this could be tested and the results trusted would be in a controlled environment at like 300 yards.. in a place like the testing they done in that warehouse years ago.. BUT.. and it's a big but.. if a guy believes in what he's doing and it gives him confidence at the shooting bench then no matter what it is he's going to shoot smaller groups.. just my thoughts.. confidence in what your doing goes along ways
Quote from: autoxforfun on July 18, 2023, 07:35:27 PMWhat hit me immediately was that the first thing he did was weight sort the primers. Is there agreement here that weight sorting has a bigger impact than seating depth?
I haven't tested Bob to have an answer I'm comfortable with. For competition I weight sort primers. Not necessarily to get them all in the identical weight spot, but rather to cull those primers that are excessively heavy or light. The light ones are what I'm really after. The process is a PIA and sometimes you can sort 500 without finding a real bad flier. On average with BR4s I will find one out of 500 that is 20% or more deficient in weight. I dropped a round 8" below my group at 600 in a match and I don't want that to happen again. The extra benefit beyond finding that under charged primer is knowing that all the primers I'm using in my record rounds are the same. It gives me confidence if nothing else, but I do believe there is an advantage to consistent primer energy at ignition.
There are folks who argue you can fine tune a load using primer seating depth. I don't worry about it. If I'm getting a good tune at my favorite depth I don't hunt around for something better.
So what's the consensus on a reasonable starting point for primer crush, .003" ?
Quote from: VA-XBolt on July 19, 2023, 07:30:17 AMSo what's the consensus on a reasonable starting point for primer crush, .003" ?
I would say it depends on your fire control and primer choice.....for myself, I have found Federal primers to be more depth specific and CCI's are like dumb primers, they are pretty good about anywhere. I shoot a lot of CCI's but have had excellent results with Fed's as well.
I will say this...any amount of crush is better than any primer jumping.
Quote from: autoxforfun on July 18, 2023, 07:35:27 PMIs there agreement here that weight sorting has a bigger impact than seating depth?
I wouldn't go that far...I would sort primer weight before I sorted bullet BTO. ;D ;D ;D
Quote from: gman47564 on July 18, 2023, 08:19:45 PMMy thoughts on this.. I know their not worth much.. in my mind trying to test primer seating depth outside in conditions at distance is futile.. theirs just too many variances at play to honestly say yep this is the perfect primer seating depth.. to me the only real way this could be tested and the results trusted would be in a controlled environment at like 300 yards.. in a place like the testing they done in that warehouse years ago.. BUT.. and it's a big but.. if a guy believes in what he's doing and it gives him confidence at the shooting bench then no matter what it is he's going to shoot smaller groups.. just my thoughts.. confidence in what your doing goes along ways
Couldn't that be said about all testing?
Quote from: gman47564 on July 18, 2023, 08:19:45 PMMy thoughts on this.. I know their not worth much.. in my mind trying to test primer seating depth outside in conditions at distance is futile.. theirs just too many variances at play to honestly say yep this is the perfect primer seating depth.. to me the only real way this could be tested and the results trusted would be in a controlled environment at like 300 yards.. in a place like the testing they done in that warehouse years ago.. BUT.. and it's a big but.. if a guy believes in what he's doing and it gives him confidence at the shooting bench then no matter what it is he's going to shoot smaller groups.. just my thoughts.. confidence in what your doing goes along ways
I guess I have to disagree. You pick your condition become familiar with your gun and load and test it.
4 or 5 sets of 3 shots keeps you from getting into a goofy condition if your testing in the calm to begin with. The same limited sample size takes barrel heat and bore foul out of the equation.
The distance itself is the great equalizer that tells all.
Your reloading, equipment and gun handling have to be on point but I've learned far more at distance than I've ever learned up close.
I'm not going to debate it or argue about it but I've seen too many guns tuned at distance to believe it's futile to test there.
Anything can be tested at distance if you construct the test to isolate what you're looking for.
It goes back to what I said yesterday about KGs test you can easily throw too many samples at something as well as not isolate what you're really looking for in a test.
I'm going to try and test primer preference in the next two weeks and possibly seating preference. I'll share results no matter the outcome.
There's a pic in this thread of a seating preference ladder that clearly shows a preference as well as a coming in going away factor that I think shows the "node" not a blind squirrel finding an acorn.
Quote from: VA-XBolt on July 19, 2023, 07:30:17 AMSo what's the consensus on a reasonable starting point for primer crush, .003" ?
In the limited testing I've done on CCI 400s
.003" crush has produced a noticeably smaller group than 2 4 5 or 6 and I've had others tell me the same. I've not tested it on other primers.
I'd like to but time and conditions are the limiting factors.
It would be easy to load up tests and be ready for the condition but if I'm testing it it's going to be on the actual match brass for that intended gun, powder, bullet combination so I don't want to get that brass out of rotation.
(https://i.postimg.cc/15CTHNjX/IMG-20220706-175856147.jpg) (https://postimg.cc/TpbC2hGv)
That's the pic from the test a year ago.
Same gun, brass, barrel, powder lot, bullet lot, same load that won the 2022 Rendezvous. Test wasa couple weeks after the match on leftover brass that was sized for the match.
Conditions were very good. This is my argument for being able to test at distance. I kept as many, possibly all the controls in place that won that match and set a 16 target agg range record of 3.522"
The primers in the rounds I shot at the Rendezvous were seated .0035"
My confidence in myself, the gun and the load could not have been higher for the test and before retrieving the target I felt good about all the shots.
The test is valid as far as I'm concerned.
If on the other hand a person's gun, gear and load are not proven and predictable and shot that same ladder I would have to say "well that's interesting" I guess 😂
Ironically purple (5) with the best SD ES is the worst group of the test.
2-3-4 is a dandy 9 shot group that shows very similar on the ends and shrinks in the middle then it jumps out and gets big.
Quote from: jvw2008 on July 18, 2023, 08:32:23 PMI haven't tested Bob to have an answer I'm comfortable with. For competition I weight sort primers. Not necessarily to get them all in the identical weight spot, but rather to cull those primers that are excessively heavy or light. The light ones are what I'm really after. The process is a PIA and sometimes you can sort 500 without finding a real bad flier. On average with BR4s I will find one out of 500 that is 20% or more deficient in weight. I dropped a round 8" below my group at 600 in a match and I don't want that to happen again. The extra benefit beyond finding that under charged primer is knowing that all the primers I'm using in my record rounds are the same. It gives me confidence if nothing else, but I do believe there is an advantage to consistent primer energy at ignition.
There are folks who argue you can fine tune a load using primer seating depth. I don't worry about it. If I'm getting a good tune at my favorite depth I don't hunt around for something better.
Possibly I'm splitting hairs here but I've never heard anyone claim they tune their load with primer seating depth. I've always understood it one of those things you test once for preference and done.
Out of curiosity what is your preferred depth because if you haven't tested it I'm betting your running ,+.003"
I think I know the answer to this next question but will ask it anyway because some people confuse these terms easily.
For myself I'm seating to touch +.003" crush, tension or whatever anyone wants to call it.
So I'm assuming when you say "favorite depth" you mean touch +.00? Yes or no?
I'm only asking this because some people are going to confuse "depth" for below flush and don't want someone to chase that unknowingly.
After setting the crush I'll use the below flush measurement to further sort hopefully further improving ignition timing.
In my opinion if a uniformed pocket with a specific crush on a primer makes more consistent accuracy then below flush consistency would have to further uniform the system.
In a box of 45 I will sort them to a .0015" below flush variance. I usually get 30-35+ that fall into that range. The rest are foulers or sighters
"Possibly I'm splitting hairs here but I've never heard anyone claim they tune their load with primer seating depth. I've always understood it one of those things you test once for preference and done."
That info came directly from Greg Dykstra in a personal phone conversation. He also discussed it in his video with Cortina. For those wondering Greg Dykstra is the inventor and producer of the Competion Primer Seater which Dave and I have discuss here on the form. Greg has indicated he believes a tuned load can be further tuned by adjusting primer seating depth by a known amount.
" Possibly I'm splitting hairs here but I've never heard anyone claim they tune their load with primer seating depth. I've always understood it one of those things you test once for preference and done.
Out of curiosity what is your preferred depth because if you haven't tested it I'm betting your running ,+.003"
I think I know the answer to this next question but will ask it anyway because some people confuse these terms easily.
For myself I'm seating to touch +.003" crush, tension or whatever anyone wants to call it.
So I'm assuming when you say "favorite depth" you mean touch +.00? Yes or no?
I'm only asking this because some people are going to confuse "depth" for below flush and don't want someone to chase that unknowingly."
Yes touch plus either two or three depending on the brass and primer used. I have not done a direct test as you posted so I don't believe it would be appropriate to tell Bob I've specifically tested it. My choice of depth has come from tuning loads. I seem to get best results @ 2 thou below flush with Alpha brass that has not had pockets uniformed and 3 thou for those that have. Since I measure primer pocket depth and know the cup height, it's pretty easy to hit touch and then whatever additional is needed. I believe some primers within a lot are more difficult to seat than others. Especially if there is variability in thrust applied to the CPS arm. Knowing cup and pocket dimensions, I'm not happy when the gauge says I'm at minus 3 and the measurement out of the seater is minus 2. IE - I trust my direct measurements more than the dial gauge attached to an arm apparatus that will flex. I have found the virgin pockets can be sticky enough to make the gauge on the CPS lie. After uniforming and at least one cycle, there is much better agreement.
@jvw2008 Yes I agree virgin pockets are liars 😂
I figured you were in the touch +2-+4 range, so if I'm understanding you right you're seating to a crush value So that you end up with a desired below flush value you've tested to be a better load but have not tested crush value to come up with a preferred crush value correct or I misunderstood you?
I follow your thoughts on ignition timing and if they're all the same below flush with the same crush within the set I can rationalize the advantage but how do you account for rim thickness variance or is that the one variable beyond your control?
Yes with the CPS the rim thickness is out of control. If bulletjock's friend has developed a primer seater that is convenient to use and accounts for varying rim thickness I would love to see it.
Relative to rim thickness variation, if your test results are repeatable, it would appear there is an optimum window or range of seating depths that perform well. If so, possibly varying rim thickness is not a huge issue.
I would also suggest that if you are assessing true seating using known pocket depth and cup height, variation in rim thickness is taken out of the equation. The other elephant in the room though is how much of the bottom of the primer cup is flattened by the seating force resulting in a primer cup that is no longer as tall as it was before seating.
These are the thoughts I have pondered, made me shrug my shoulders and say if it's good on target, I not going to worry about it.
Yeah agreed there are things out of our control and things we just don't no. Nothing you can do about them until the next thing comes along.
I'm hoping Bullet Jockey will pop in and tell us a little more about his friend Keith's primer seater.
Quote from: jvw2008 on July 20, 2023, 09:44:29 PMI'm hoping Bullet Jockey will pop in and tell us a little more about his friend Keith's primer seater.
Keith and I aren't teammates anymore and has moved on from Fclass apparently (he's shooting PRS). He had some sort of agreement with 21st Century at one time to bring it to market, no idea where that's at now.
It's a fine tool that will seat primers to within .0005 consistently and take rim thickness out of the equation. I'd buy one in a heartbeat.
Quote from: Bullet Jockey on July 21, 2023, 09:12:11 AMKeith and I aren't teammates anymore and has moved on from Fclass apparently (he's shooting PRS). He had some sort of agreement with 21st Century at one time to bring it to market, no idea where that's at now.
It's a fine tool that will seat primers to within .0005 consistently and take rim thickness out of the equation. I'd buy one in a heartbeat.
Me too if they ever become available let me know.
I shot the two primer preference ladders this morning @ 600 in the Bat & Panda.
Using the best load I've found to date for each.
Calm 50° # 7 am
I've been shooting 400s in both. Hard to ignore the lack of vertical in the BR4s on both guns. I'll probably run powder ladders with BR4s tomorrow morning.
(https://i.postimg.cc/YC16Gw0r/IMG-20230721-075633235.jpg) (https://postimg.cc/k2g6zzWz)
(https://i.postimg.cc/D09G0CK4/IMG-20230721-075943828.jpg) (https://postimg.cc/4H1yFQyX)
Here's the other thing about sample size, I had 17 rounds a piece in these tests. So then I test powder, then seating then if I test crush preference that's another 60 rounds on each barrel, makes 80 rounds down the tube testing if I were shooting 5 shot samples that puts it over 100 testing.
Unless you're in the business of just wearing out barrels tests need to be done in a manner that limit rounds fired on conditions you can trust to keep your round counts as low as possible on the barrel.
After you become familiar with a platform you can get a feel for a small sample test in the right conditions.
These two tests for instance I'm 99.999% the vertical is what it is. The windage maybe more like 90%, off a rest & bag it's much it's much more likely to pull one left or right than up or down in my experience.
Agreed. I understand the statistical argument for larger and larger sample size but I'm totally opposed to it for a couple of reasons. One I'm never going to accept a small sample (3 rounds) without repeating it for confirmation. Two I can round three rounds in 5 seconds and "statistically" improve my chance to catch the same range condition for all three rounds.And three when I'm running a first ladder I'm looking simply for a suggestion of what internal ballistic condition looks promising. When I go to 5 and 10 rounds for record on target in a match, I either prove or disprove my ability to read three round groups. If I'm going to shoot out a barrel it's going to be in matches.
Couple things on your primer selection. Yes the BR4 horizontal is good. But so is the extreme spread. The Federals look in second place there. Also isn't it interesting the 450s did not produce an average higher velocity than the others. I've fallen into a pattern of using the 400s for my 6mm plinking on steel and saving the BR4s for comp. I've been working with a friend on tuning a 6x47 using a relatively slow burning powder to acquire a 90% + case fill. Even with that powder the BR4s produce as much velocity as the 450s igniting 42+ grains of powder.