I just finished reading this thread:
BH, your notion that "there is absolutely no such thing as ONLY bumping the shoulder as implied" seems a risky declaration. Do you think it isn't possible? You might remember my mentioning of testing loads for 'MyMax'. I always do this, and it's here that I produce 3 cases which I send to...
www.longrangehunting.com
In many of the posts, users mention "properly set up dies". What specifically does this mean?
A little back story on myself...I have been reloading for a number of years now. No competition shooting or anything like that but lots of hunting here in the west.
Recently I had some cases split (case head separation) on my 7mm mag after only 3-4 firings. I've always loaded for this rifle the same way (once load development was done, which didn't take long). Nothing extreme, well within max published load, shoots fantastic in this rifle.
160gr Accubond over 61gr of RL-22 using Federal or Winchester primers.
So, I begin researching why this may be happening. Thin brass (bad batch), excessive chamber specs, over working the cases, etc. all come up as likely culprits.
I have always FL sized my brass after each firing. Many suggested I back my dies out so that I am just "bumping" the shoulder back about .002" or so. Fair enough, easy to do.
The thing that has me really hung up is that my fired brass measures 2.1185avg. During the sizing and "bumping" process it grows to as much as 2.124 before I make contact with the shoulder and it begins to shrink. So in my mind, the stretching (damage) is already done before I even get the neck sized.
New brass measures 2.101, btw.
So, I buy a neck sizing die. I haven't used it yet but people are recommending I not use it for hunting loads...back to square 1.
BTW, the rifle will close on cases 2.120 and maybe even higher, I ran out of fired brass before I got to the top end of its chamber dimensions.
So am I supposed to be bumping shoulders .002 +/- from my fired case size (2.1185) or from the max my chamber will accept or from the max length my die makes them become (2.124) during the sizing process?
So confused. Sorry for the long post but if I've learned anything from forums, it's that more information usually generates better help.
Thanks.