Help Support Long Range Hunting Forum
What do you see on the brass for pressure signs? Primer, ejector, bolt face, scoring, etc..
Are you trimming cases back every time you prep them? Are you bumping the shoulder at least .002? Are you base data measurements getting down to 0.532? This datum line is 0.2 up from the base. Look at the SAAMI drawing and you'll find it. With Hornady brass and the match grade Hornady bushing die I found if I bumped the shoulder .004-.005 I could get this number down to a size that allowed normal feeding closing and extraction. It may or may not work for your setup.
You sir I believed saved the day! I also am using the Hornady bushing dies and so I started messing around again with shoulder bump and going from my original .002 bump to .004 bump and it was enough to make these hard to chamber 5 round lapua brass cycle like virgin brass again. I was about to dive straight into an AW2 reamer, $350 seating dies, etc.
I'm glad it worked for you. It fixed my father's hard to close multi-shot brass. He is also using Hornady. He can only get his down to 0.533 but it seems to work. I played around with the whole shoulder bump settings one day hoping it would be enough to squeeze that base area down as getting more brass was and still is very hard right now and we needed to shoot a bunch to allow my wife practice time for a hunt we did last year. It has saved about 200 cases. Before I got the cases fixed, I was even having over-pressures from known good loads.
I don't know about the shooter, but the rifle shoots nice. I had 2 built off XM actions for the long heavy bullets. I sold the one that was had a BDL plate. Looking to build another on a mag feed, but components are hard to come by. Thanks & you have a great evening!
.004 total… explain your thoughts ..
My thoughts on the issue are if you bump too far, in addition to increasing tolerances you're risking thinning out the lower case walls above the web:
Id say you've found it! Excellent group!
You are correct about potential case issues. But short of spending more time and money this is an easy fix I've fired 200-250 rounds sized like that reusing cases 3-4 times with no issue. Case head separations are pretty easy to spot before they happen, so they really are not a big deal. We used to get them in STWs back in the 90s all the time. You see the line forming and just toss the case. Anyway I'd rather get 4-6 turns out of a case then 2. Especially now with brass shortages.My thoughts on the issue are if you bump too far, in addition to increasing tolerances you're risking thinning out the lower case walls above the web:
Incipient Case-Head Separation — How to Detect the Problem « Daily Bulletin
We are re-publishing this article at the request of Forum members who found the information very valuable. If you haven’t read this Safety Tip before, take a moment to learn how you can inspect your fired brass to determine if there may be a potential for case separation. A case separation can...bulletin.accurateshooter.com
This point is somewhat implicit in Vance's post - with the 6.5 PRC the problem is needing to size the datum line on the base down (due to the chamber tolerance being too tight in the design), and to get this particular Hornady die low enough to do that the result is the shoulders moving .004-.005. It's a dimension problem in the die (in that the die doesn't size the datum line small enough until the shoulders are too low) so you're trading a current problem for a potential new problem.
The solutions I would pursue are either a better die that sizes the datum line with less shoulder bump, or the AW2 reamer to fix the chamber dimension issue that gives rise the die needing to size more. That doesn't mean "maybe have to buy brass more often" as the cost of oversizing the case isn't a viable solution also, just not the one I would want.
My custom dies have been running about 4 months from order to door.
It might but the size of the PRC case is basically the diameter of belt. I was hoping Hornady or Redding would come out with a something like a small base die like you use in 5.56s. This is an issue for both the 6.5 PRC and the 300 PRC. Those datum lines are the same on both cases.
