Which First Bullet Seating or Powder Charges

[SmokeLessWonder]

Which do I start testing first, getting the correct seating or doing a load test like the Satterly.
I"m loading 147gr Hornady ELD Match, into StarLine srp brass, my primers are cci 450s, and the powder will be H4350.
Thanks, any info will be helpful.
Ray

[gman47564]

With the eldm's i like to start with a set seating depth of .020 off the lands and test powder.. welcome to the forum..

[The Marshall]

Whatever variables that you control and want to change, only change one thing at a time. Example: keep everything the same put work on different seating depths. A wildcard in this is the barrel temperature. There are two different ways to see it.  —— you can fire three rounds as quickly and accurately as you can, then leave the barrel to cool or shoot and wait for the barrel to cool before the next shot. I use the second method. It takes longer but is better at showing cool barrel accuracy and that is what I want as a hunter. For a match shooter, some might want to know how groups spread with a warmer barrel.
H-4350 is close to the burning speed of RL-17 and IMR 4451 so if you're looking for another powder due to availability problems, these are two that can fill in without a lot of load testing.

[SmokeLessWonder]

gman, thanks for the info. I did plan to start out at .02 off the lands, but wasn't sure if that would or could be sufficient for the Satterly test.
And as for temp, I got a couple of those temp strips for my barrel and a battery operated, air blower to cool the barrel after a couple of shots

Thanks for the info, gents. You have been most helpful.
Ray

[bikemutt]

The Satterly (sp?) test is velocity based if I recall correctly. You can use charge weight, seating depth, or any other variable you want. I would run the test at least twice in order to validate.

[JASmith]

Let me rephrase the OP's question:  How much does the optimum seating depth change when one goes from one powder to another?

If the preponderance of experience indicates it changes enough to make a difference, then starting 0.020" off the lands allows a consistent start to things.

If, on the other hand, there is experience suggesting that the optimal seating depth is the same or close to the same for most powders, then starting by optimizing seating depth as the first step might reduce the number of trips to the range during load work up.

[Henryrifle]

I have tried a lot of different ways to make load development more efficient but before getting to my process there are numerous factors to consider.  Here are just two: the first is experience which, could be your own or 'the collective.'  Experience can greatly reduce the amount of testing because you have an idea of where the rifle is likely to shoot.  Another is that if this is a new barrel you need to get somewhere around 100-200 rounds down it before velocity settles down.

Your specific question was about seating depth vs. charge weight.  What follows is my opinion and my process there are many others that are perhaps better to much better.

• Use a known decent seating depth or magazine length if that is a constraint.
• Shoot a Satterly to determine where the velocity flat spots are.  There are usually two good and obvious ones.
  
• Once you've identified the 'likely' nodes by the flat spots, test around those spots using the OCW method to find a stable and low SD.
  
• Once you have that, start testing seating depth.  I used to go in larger increments but now I test every .003 starting in the lands to .05 or even .075 off the lands.
  

Here is a shortcut based on my experience with 6.5 Creedmoor for your specific components:  my experience with Hornady ELD projectiles is that .02 and .03 off the lands is as good a place to start as any.  Similarly, using the 147 ELD-M projectile in 22" to 26" barrels you are looking for a velocity in the 2680 to 2750 FPS range.  And finally with H4350 depending on the speed of your barrel the charge weight is likely between 40.5 grains and 42.5 grains.

Henryrifle

P.S.  There are those that believe that in heavy match-type barrels that seating depth controls accuracy and you select the velocity that meets the requirements of the match and has an acceptably low SD.  I have tried this approach seriously two times and this did not work for me.

[SmokeLessWonder]

Henryrifle, I'll take your suggestions but I'm still struggling with getting the correct seating. Seem as if like when I measure my base to ogive using a comparator and modified case, my OAL is too long, and rounds will not chamber.

I'll keep backing off until I can seat rounds then back off an additional .02"
thanks Ray

I have tried a lot of different ways to make load development more efficient but before getting to my process there are numerous factors to consider.  Here are just two: the first is experience which, could be your own or 'the collective.'  Experience can greatly reduce the amount of testing because you have an idea of where the rifle is likely to shoot.  Another is that if this is a new barrel you need to get somewhere around 100-200 rounds down it before velocity settles down.

Your specific question was about seating depth vs. charge weight.  What follows is my opinion and my process there are many others that are perhaps better to much better.

• Use a known decent seating depth or magazine length if that is a constraint.
• Shoot a Satterly to determine where the velocity flat spots are.  There are usually two good and obvious ones.
  
• Once you've identified the 'likely' nodes by the flat spots, test around those spots using the OCW method to find a stable and low SD.
  
• Once you have that, start testing seating depth.  I used to go in larger increments but now I test every .003 starting in the lands to .05 or even .075 off the lands.
  

Here is a shortcut based on my experience with 6.5 Creedmoor for your specific components:  my experience with Hornady ELD projectiles is that .02 and .03 off the lands is as good a place to start as any.  Similarly, using the 147 ELD-M projectile in 22" to 26" barrels you are looking for a velocity in the 2680 to 2750 FPS range.  And finally with H4350 depending on the speed of your barrel the charge weight is likely between 40.5 grains and 42.5 grains.

Henryrifle

P.S.  There are those that believe that in heavy match-type barrels that seating depth controls accuracy and you select the velocity that meets the requirements of the match and has an acceptably low SD.  I have tried this approach seriously two times and this did not work for me.

[gman47564]

ray are you sure its the bullet keeping it from chambering or is it the shoulder not being set back enough to allow it to chamber... will a empty case thats ready to load chamber ok ?

[SmokeLessWonder]

gman.
Sorry for the delay. But two of the first things I did was 1) take a piece of Starline and brass and chamber it w/o a bullet seated, 2) I took a fired piece of Remington brass and chamber it. There were no problems in either case.
I did something wrong with my measurements and will fix it and give an update this weekend.
Thanks

ray are you sure its the bullet keeping it from chambering or is it the shoulder not being set back enough to allow it to chamber... will a empty case thats ready to load chamber ok ?

[SmokeLessWonder]

Update:
I did the following:
1) I removed the firing pin from the bolt to make sure I had the right amount of force to close the bolt;
2) I took a piece of ammo that I had loaded and seated with a 147gr Hornady bullet and tried to chamber it;
3) the bolt was tough to close and to make matters worse, I had problems getting the round out the chamber. (mistake)
4) I checked the OAL on this round and found it to be 2.919 (this is something I should have done from the start)
5) I seated the bullet lower about a .25" at a time to find if I could chamber and remove the round. No matter what I did the bolt closed real stiff on that round but I could unchamber w/o a problem.
6) I was confused and I checked if I had the same problem with my 140gr Remington rounds. I did not. Even when the OAL on my 147 was less that 2.800 the problem round would not chamber without a stiff bolt.
7) I tried other rounds from that I created to see if they had a stiff bolt when the OAL was about 2.810, all but one were OK and did not have a stiff bolt closure. This may have been a round that I tried to chamber at the range, had a VERY stiff bolt, and I could not extract the live round without a lot of trouble.

Before I make anymore rounds I will get some 147gr Hornady ammo and use their measurements as my starting point. BUT I'll have to keep my OAL to around 2.8 (which is what the loading sheet specifies) regardless of what the CBTO measurement is.

[bikemutt]

This sounds suspiciously like a problem I ran into. My brass had developed a donut such that even fired brass would have "feel" when lifting the bolt (firing pin and ejector removed). It got worse; bumping the shoulder 2 thou still had the same feel. Just to be clear, this is without seating a bullet, it was just the brass.

I'm no expert but you shouldn't have to seat regardless of true CBTO unless you are up against feeding constraints.

[mnbogboy]

Agreeing with possible "donut".  The long bullet passing the neck/shoulder junction pushes the donut outwards could be causing the interference.
Coloring the case with a Sharpie and chambering would show this as a "shiny" spot. On the empty case springback carries it back in.
How many firings/sizing on this brass?  Normally a donut doesn't show up early in case life unless it was made from another case.

The Sharpie test may also show any other interference including possible bullet interference as in a carbon ring or case mouth interference.

[rardoin]

One other common cause of resistance on closing a stripped bolt on a 'dummy' round is eccentricity of the seated bullet.  Roll the round on a flat surface slowly and see if you can see any wobble of the bullet tip.  If you can see it visually then it will affect the feel on bolt closure.  Been there, done that, and the hair will NOT grow back .

[SmokeLessWonder]

One other common cause of resistance on closing a stripped bolt on a 'dummy' round is eccentricity of the seated bullet.  Roll the round on a flat surface slowly and see if you can see any wobble of the bullet tip.  If you can see it visually then it will affect the feel on bolt closure.  Been there, done that, and the hair will NOT grow back .

thanks rardoin
I tried that out with no noticible wobble. That's a good way to check if your bullet is in at an angle though. I just think I seated them too long. Once I seated most of them around 2.810 they were fine. Now the ones that were too long and I force them into the chamber, I'll just resize them before I try to seat them again.