Primer pocket test forthcoming.

I'm using a RCBS Auto Prime modified with a Hollands Perfect Primer adapter tool to put them in and an Accuracy One Precision Primer Gauge to measure seated depth. I've been using them for a while now and produces pretty good results. Repeatability is good.
Why not use the included Hollands gage? It looks pretty nice.
 
Seems to me that the variability of primer pocket "tightness" and flash hole size/length could introduce some static into the numbers, not to mention the primer consistency. That and neck tension…Still, I'm interested in your findings.
 
I'm getting ready to do a primer pocket test in the next week or so (weather permitting). A little different type test.

Purpose of test is to see if there is any difference between cases that have a .127 pocket and cases having a .130 pocket depth.

All primers will be seated .003 -.005 below case head. I am using -14, -15, and -16 LC 308 cases. All cases are full length sized with neck sized bushing using the RCBS Match Master dies. Sholder bump is
.002-.004. All cases trimmed to 2.005. Powder is IMR 4064, primers are CCI 34, and bullets are 175 SMK AND 168 SMK. 70 rounds each bullet weight. Powder charges will increase from 42.5 to max of 45.0 at .5gr increments. Bullet seated depth per Sierra reccomended depth. COAL is 2.805-2.810.These cases are new, never fired. Gun is a new just broke in Bergara HMR PRO

I'm curious to see differences (if any). Expecting overpressures at some point and primer issues also. Testing limits of applicability. We'll see.....

Will report back.
I'm locked in to see your results. I've used a RCBS hand priming tool for 30 years exclusively and with good results and seat them 3 to 5 thou under the case head. I do weigh primers and batch them accordingly. I've been able to keep ES and SD in single digits but if there's a better method, I'm all ears. I believe (with my limited knowledge) neck tension plays a larger factor in consistency than primer depth.
 
I'm with Mike M on powder .5 can be alot when you are approaching "Max" for your gun....just me I go .3 leaves a little wiggle room.
My test limits the powder max before I start. I decided to not load to published max at the beginning to avoid issues. I'm stopping .6 from published max. Which is 45.6. I'm only loading to 45.0. I'm not so much looking at grouping. I want to know what the net effect of different primer pocket depth is. All of my primers are touching the bottom. Others have done similar tests, but all with the same cases having the same pocket depth. Different makers of cases manufacturer them to different depth. Ive got cases with pocket depths ranging from: .125 from federal, 127 from LC, .129 from hornady, and .130 from lapua. (I did sort all cases to the same depth prior to test.) I'm only dealing with ones from the same lot and make (LC) and only two selected depths: .127 and .130 which represents the bulk of my case stash. As opposed to primer seated depth with relation to crush. Not testing the actual crush. They all touch the bottom. The cases I'm using came from a govt contract cancelation. They were pull downs and new, unfired. I cleaned them. which was a pita considering the primer and neck sealer used. (I use xylene here. Works better than acetone.) Then did a full length size w/neck bushing. Trimmed all cases and did the chamfer/debur. Didn't need to do annealing because they had never been fired. After all done, I inspected all one by one using my Stareett caliper, Forster case gage, and checked bump. Which was 2-3 thou. After this, I'm just curious what will happen.
 
Seems to me that the variability of primer pocket "tightness" and flash hole size/length could introduce some static into the numbers, not to mention the primer consistency. That and neck tension…Still, I'm interested in your findings.
It could. But in my case, all cases are new, unfired. I weight sorted all of them. And ensured all had the same height. (.126). I really have tried to limit, as much as I could, any variability that I could control. Sounds a bit self defeating if I didnt try. We' ll see...
 
I suppose you could pin gauge the holes to ascertain uniformity. Interesting conversation with my dad the scientist. He was all geeked out about the lengths we go to to get the "best" hand loading system we can. He loved all the data and variables. That said, he mentioned I'd be better off spending more time at the range vs the bench. He's not a shooter either.
 
I suppose you could pin gauge the holes to ascertain uniformity. Interesting conversation with my dad the scientist. He was all geeked out about the lengths we go to to get the "best" hand loading system we can. He loved all the data and variables. That said, he mentioned I'd be better off spending more time at the range vs the bench. He's not a shooter either.
Sometimes I feel the same, then my ocd kicks in. (Apologies to ocd sufferers out there.)
 
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