I just pulled some brass out of my tumbler and started sorting the 40S&W brass to load a new batch. This will be the third time they've been loaded. I measured the whole batch before I shot them last time and I'm damn near positive the brass all measured between .840 and .850. Now, a significant portion of the brass is measuring about .835-7. I don't get it. Did my brass really lose length during the firing process? Should I throw all that brass away or just load the short brass?
Scratching my head on this one
- Thread starter ZLBubba
- Start date
Re: Scratching my head on this one
The brass will lengthen after resizing. A little short is ok if just slightly less than minimum spec.
TC
The brass will lengthen after resizing. A little short is ok if just slightly less than minimum spec.
TC
Re: Scratching my head on this one
Straight wall brass doesn't "grow" like bottle neck brass. It "settles", watch for thinning at the top if anything.
Shoot away merrily.
Cheers,
Doc
Straight wall brass doesn't "grow" like bottle neck brass. It "settles", watch for thinning at the top if anything.
Shoot away merrily.
Cheers,
Doc
Re: Scratching my head on this one
<div class="ubbcode-block"><div class="ubbcode-header">Originally Posted By: ZLBubba</div><div class="ubbcode-body">I just pulled some brass out of my tumbler and started sorting the 40S&W brass to load a new batch. This will be the third time they've been loaded. I measured the whole batch before I shot them last time and I'm damn near positive the brass all measured between .840 and .850. Now, a significant portion of the brass is measuring about .835-7. I don't get it. Did my brass really lose length during the firing process? Should I throw all that brass away or just load the short brass? </div></div>
When you measured them before tumbling they had a slightly frayed edge from being sized , chamfered , tapered , crimped , fired . During tumbling that edge is pounded back down a bit and they measure shorter. After a few reloads a small amount of brass can be lost from the mouth of pistol cases more so than a rifle case. So as time goes on they can shorten a bit because low pressure pistol cases in general don't flow brass forward as much as rifle cases can.
<div class="ubbcode-block"><div class="ubbcode-header">Originally Posted By: ZLBubba</div><div class="ubbcode-body">I just pulled some brass out of my tumbler and started sorting the 40S&W brass to load a new batch. This will be the third time they've been loaded. I measured the whole batch before I shot them last time and I'm damn near positive the brass all measured between .840 and .850. Now, a significant portion of the brass is measuring about .835-7. I don't get it. Did my brass really lose length during the firing process? Should I throw all that brass away or just load the short brass? </div></div>
When you measured them before tumbling they had a slightly frayed edge from being sized , chamfered , tapered , crimped , fired . During tumbling that edge is pounded back down a bit and they measure shorter. After a few reloads a small amount of brass can be lost from the mouth of pistol cases more so than a rifle case. So as time goes on they can shorten a bit because low pressure pistol cases in general don't flow brass forward as much as rifle cases can.
