It requires removing the ejector and firing pin from the bolt so that there is no tension when closing and opening it.
The other technique is one we all probably use or have tried; the Hornady OAL gauge, aka the Stoney Point gauge. I won;t go into the details of this technique as it's so widely used.
The bullet used here is a random sample Hornady 140 gr Match BTHP. The rifle is a broken in Browning X-bolt Target.
I measured CBTO with the Hornady gauge 10 times, the results appear in the chart below. Frankly, I was surprised at the spread over these measurements as I consider myself an accomplished OAL gauger, lol, guess I know better now. I included an 0.006 adjustment factor derived by considering the generic Hornday case base-to-shoulder versus the actual case base-to-shoulder.
For the bolt technique I followed the video, seating the bullet down by 0001 until there was absolutely no "feel" or click when lifting the bolt. For CBTO I used 0.001 above this point because that's precisely where the bullet contacts the rifling.
The yellow rows on the spreadsheet show the difference between the two techniques for average, median and mode numbers using the Hornady gauge.
The best case, using the mode, is 0.013 difference versus the bolt method. If we use the average there's a 0.020 difference.
Looking back in my notes I've been using a Hornday gauge measurement for this rifle/bullet of 2.202, how's that for throat erosion?
If I believe the bolt technique is accurate, and I do, that means when I say my rifle likes these bullets seated 0.013 OTL, what I'm most likely saying is it likes 0.000 OTL or jam. That's best case, maybe it likes +0.007 jam.
Here's an interesting side note: I could not use Alpha brass for the bolt technique. Even when body and neck sized they fit sufficiently tight in the chamber that there's always bolt lift click, even without a bullet. I had to use some Starline brass which worked just fine.
A couple weeks ago I was annealing a batch of brass and had a sinking feeling that I'd annealed a piece twice, the second time before it cooled down. Looking at that pathetic pile of brass in the baking tin I use for hot brass, I was filled with anxiety wondering how I'd ever find that piece, if it even existed. I set the brass on a white towel, all in a row and voila, I found ole' charbroil charlie
Fast forward to last Saturday, I get to the end of an annealing session, I know I started with 25 pieces but AMP says 24 annealed. Here we go again After scouring the pin tumbler and my entire reloading room looking for the missing piece with no luck, I decided to count them on the white towel; 25 pieces Upon further inspection, there she is, staring right back at me
I got one of these for Christmas based on recommendations I read here. From a functional standpoint the device works well, I like that. But, this has to be the most bench-unfriendly piece of reloading gear I've come across.
It needs to be mounted to the bench more or less close to the edge, now there's a horizontal handle waiting to gut-gore me every time I walk by.
Then there's the primer tube sticking up in the air just waiting to arm-stab me every time I reach up for something on the top shelf.
I figured out a way to make the handle a non-issue by moving the tool.
The primer tube I think would work if I pull the pin and remove it but, how to do that without half a dozen primers scattering? In other words, is there a way to "unload" the primer tube?
The next time I load this batch of Alpha brass will be #11. It hasn't grown, primer seating feels positive and consistent, and I can't see any sign of splitting or other stress indicators. I pin tumble and anneal every firing, body size with 0.001 bump and collet neck size. No hot loads here. I compete against myself so not the end of the world if I lose a match, I'm used to it
At this point I feel as if I got my money's worth. Would you guys keep running them until the weakest link indicates end of life, or just call it good and retire them to enjoy the sunset years?
While chasing a runaway rabbit down a hole today, I pulled apart Lee and Forstner seating dies so I could get a better feel for the seating stems inside the beasts. Other than the Forstner was naked-eye free of tooling marks inside the stem whereas the Lee was more rough, and they attach to the die differently, I couldn't see any obvious differences.
Is there a seating stem standard which defines the profile inside the stem? Is it caliber-dependent?
I know some manufacturers offer special stems for VLD-style bullets, I'm wondering more about regular bullets.
Choosing the "master" or reference bullet. What's the best way to select this bullet? I imagine if I pull a bullet from the box and it just happens to be the "outlier", it seems to me that might make more work for me than necessary.
When a bullet measures right between say 0.001 and 0.002, so 0.0015, should I round up, round down, or doesn't matter just do it the same way every time?
I like everything about the rifle range I shoot at except for the benchrest seating; every station has a barstool-style chair with caster feet. It's the caster feet that drive me nuts. I can't say how many times I'm at the trigger point-of-no-return when the chair makes a move
I'm not opposed to bringing my own seating, and I tried that with a non-caster stool but it was too tall for the benches.
What do you guys sit on at the range?
BTW, I know Grant relaxes in a BarcaLounger at his home range, that's a bit on the heavy side for me to haul around
Looking for ways to streamline the bullet seating process, I had an idea that might also parlay into bullet sorting, of sorts
Right now I use a Forstner micrometer seating die in a CoAx press.
I reset the die to the same depth each round to a point where there's very little to no chance of the first seating operation resulting in an over-seated bullet, lets say 0.005" off of target CBTO. I seat, measure CBTO, adjust the die by the difference needed to seat to target CBTO, then seat again. Most times I'll measure CBTO again because this is all about precision no? This second measurement will usually be followed by an audible phrase "Perfect!", "Crap", or "Just a tiny bit more". Regardless, I'm managing charged cases, bullets, a die and a micrometer for each loaded round.
So I got to thinking, what if I set the die once to a starting depth 0.005" taller than target CBTO just like before, then seat all the bullets, no measurements, just put 'em in a bin. Now measure CBTO for each cartridge and sort them into a handful of bins according to how much more they need to be seated to meet the CBTO target; shouldn't need more than 5 bins, probably less. I'm thinking this sorts bullets after they've been seated, I could be wrong though.
OK, now I have a few bins where each one contains cartridges who's bullets need the same amount of adjustment to meet the CBTO target. Starting from low to high, make one adjustment to the die per bin, seat the bin, move to the next bin.
At this point I could combine all the cartridges into one bin and make groups, or make groups from each bin and make warm ups from the leftovers, or whatever.
So, what's been accomplished?
Initial CBTO measurement is now a separate task from seating; no need to balance the micrometer/gauge in my lap while I try to not spill powder from carefully charged cases, hold bullets more or less straight until the die has a hold of them, then measure CBTO.
Bullets have been grouped (sorted) by their meplat-to-ogive property, the basis for CBTO seating.
The seating die, even if it's not subject to machine lash, only needs to be adjusted once per bin after the initial adjustment. Over a 50 round session that's potentially 5 die adjustments versus 51 adjustments.
As always, I have too much time on my hands even though I still work
I got an offer on Friday from Cabelas for free 2nd day shipping on qualified items, one day only. I read the fine print and determined the handgun ammo I needed was included. And I had a gift card to burn.
I ordered online even though I'd pay sales tax since the savings driving to the OR store is just not worth the drive. I get to the end on the website, enter the free 2-day shipping promo code and am told the order will be shipped free, standard shipping, estimated delivery 12/24. I punched through anyway figuring I can buy ammo at the range on the pre-Christmas shoot I promised my wife.
At this point I'm glad I saved a couple bucks, not happy about being led to believe an offer that was made, and then pulled at the last minute. But, I've ridden in this rodeo before. Dust off, get back on the horse.
Well, yesterday, Saturday, the 9mm ammo is delivered UPS (never see those guys on a Saturday around here). I figured they at least got it half-right (that's not actually what I said, but half is still in my utterance ).
It's Sunday now, watching the Seahawks game and a FedEx Express truck shows up with the rest of the ammo.
I called Ransom International this morning to inquire about one of their rests. Instead of being routed around in auto-attendant hell like I'm used these days, I spoke directly with the people who actually run the show. All my questions were answered to my satisfaction. Good advice was furnished. I was made to feel as if nothing was more important to them than assisting me. This was quite a refreshing experience for someone who's become cynical and jaded about today's version of customer service.
This has probably been tried before but I'm the type that needs to make my own mistakes
I use Lee collet dies for neck sizing, not to say there isn't anything better, but for a shooter who doesn't turn necks, it's an elegant solution that's inexpensive. I got this crazy idea to adapt a Lee collet die so it puts a full neck "crimp" on a finished round. Why you ask, good question. I ask why not? I've read about some of the benefits resulting from crimping, this is an extension of that.
Anyway, below is the basic anatomy of a Lee collet die; the piece I named the "collar" may not be the correct name; it's the tapered part that when used to apply force to the collet, causes the collet to compress the neck.
In order to use a Lee collet die to compress the neck of a finished round we need to remove the mandrel; the new mandrel will be the bullet. One problem remains; the mandrel for a 6.5 bullet is .262 or so, no way will a .264 bullet fit in the hole. So, I replaced the collar (which the mandrel runs through) with one from a 7mm-08 Lee collet die. This allows the bullet to pass freely through the collar.
I adjusted the die so that my CoAx cams over to where I can feel the squeeze without leaving collet marks on the brass. I observed a reduction in neck O.D. of about 0.0005". I get this from a Mitutoyo caliper with 4-digits, I don't believe it's that precise but, uncrimped cases measure firm to 3-digits every round. So, there's some reduction in O.D. but I don't want to overstate the case (ahem).
The first (and so far only) trial appears to favor the "crimped" rounds. This is a small sample, but I am encouraged to push on and see where it goes. These results use 7x fired Alpha brass case, wet tumbled, annealed, body sized and bumped 0.001, Lee collet neck sized with standard mandrel to roughly 0.002 neck tension. I also lubed the necks with OneShot based on observations by HufD63. All bullets were seated 0.013 OTL on top of 40.5 gr H4350 ignited with CCI BR-2 primers. Rifle used was my trusty Browning X-Bolt 6.5 CM 28" target.