|
Unread Yesterday, 07:47 PM #15
flyguy958
Senior Member
Join Date: June 27, 2009
Location: SC
Posts: 123 Interesting replies. I'm learning as I read. So the consensus would be I have a loose chamber and bump the shoulder too far back when I full length sized.
Also that if I can feel any deviation in the wall it is too much.
Guess I need to start checking a little closer for wall thickness and shoulder bump.
__________________
You can have your own opinion but you can't make up your own facts !
flyguy958 is offline
Flyguy958, “So the consensus would be.....” you have a long chamber from the shoulder of the chamber to the face of the bolt, unless, you have a full length sizer die that has been shortened by grinding the bottom of the die, just a few years ago that was the range, grinding the bottom of the die was never necessary, you could also have a shell holder that was caught up in the other rage a few years ago. The deck height of the shell holder should be .125”.
Loose chamber? Long chamber would be my guess. After firing and before neck sizing your case mirrored the chamber in length from the shoulder back to the bolt face, if by some means you could have measured the length of the case from the shoulder to the head of the case you could have determined the length of the chamber. Instead, you adjusted the die to full length size by screwing the die down to the shell holder with the proverbial 1/4” additional turn down after contact. In the process of full length sizing the reloader has the illusion the shoulder is moved back, with out considering the shoulder does not move but is erases as in part of the case body becomes part of the shoulder and part of the neck becomes part of the shoulder. Again, I do not know what receiver you have, again, some receivers can be tough on the case the first time the case is fired.
Again, bump, I suggest you avoid sizing as in limit the amount of sizing by adjusting the die not to size more than necessary. I do not know what press you are using, when sizing a case I know the length of the chamber from the shoulder back to the bolt face before firing, when sizing I adjust the die with a gap measured with a feeler gage. If I built the rifle and if I cut the chamber it is not necessary to make adjustments of the die off the shell holder, the difference between the case and chamber length will be .003” +/- very little.
Thinning of the case between the case head and case body is caused by bad habits. Then there is shoulder bump, when the shoulder of the die contacts the shoulder of the case the case is supported meaning the case body and case neck and shoulder is in contact with the die 100%. Then there is the illusion the shoulder is bumped and the assumption the shoulder is moved back. If what reloaders are doing is called bump I would call my sizing of the case wrecking, more times than not my shoulder does not move, my shoulders are erased (term described when forming). WHO KNOWS when bumping ends and forming starts?
Of the shoulder is pushed back when bumping, the case body is also bumped because the case body contacts the die FIRST! THEN! the die contacts the shoulder of the case, in that say-na-areo the shoulder is pushed up causing part of the shoulder to become part of the neck, or the shoulder locks onto the die and compresses the case, that would leave the case compressing below the case body and in front of the case head.
F. Guffey
|