Resized brass vs. new Part 2

[Multi-Tool]

I had a lot of new Win .308 brass bought in the mid-2000s. Most of it is now once fired, so I recently sent it for cleaning, resizing, trimming and headspace checking.

New cases once-fired in my Rem 700 show shoulder growth of .002”, as measured on a Stoney Point tool. This is also the measurement of the resized brass, indicating zero setback. However, the resized brass chambers and extracts without difficulty in my rifle. I have yet to fire any rounds with the resized cases.

Is the experience described above normative for brass that has been once-fired in a bolt gun? Most of my rifle reloading has been for Highpower shooting my AR-15, requiring a lot of attention to setback.

Thanks!

 

[nn8734]

Are you saying the bolt closes on the sized brass with zero resistance? If there was truely no shoulder bump you should feel a little bit of resistance closing the bolt but should still chamber without difficulty.

 

[Multi-Tool]

I don’t recall any significant resistance, but I will check it again.

 

[Doom]

Your once fired brass probably has some minor clearance due to spring back.

 

[Multi-Tool]

Are you saying the bolt closes on the sized brass with zero resistance? If there was truely no shoulder bump you should feel a little bit of resistance closing the bolt but should still chamber without difficulty.

I tested this with loaded rounds with new brass and loaded rounds with the once-fired brass. Slightly more bolt closing pressure is required for the once fired brass, but it’s close. I don’t think it would be noticeable if I wasn’t thinking about it.

 

[nn8734]

I tested this with loaded rounds with new brass and loaded rounds with the once-fired brass. Slightly more bolt closing pressure is required for the once fired brass, but it’s close. I don’t think it would be noticeable if I wasn’t thinking about it.

Sounds like it was sized with zero bump, which isnt the end of the world for a bolt gun. As long as they chamber with minimal resistance as you described you should be fine.

I might suggest you specify you want .002 shoulder bump to the brass guy on the next batch. This would give you a little clearance in the chamber and shouldn’t change anything about how the load performs but its your call.

Does the guy anneal your brass?

 

[Multi-Tool]

Sounds like it was sized with zero bump, which isnt the end of the world for a bolt gun. As long as they chamber with minimal resistance as you described you should be fine.

I might suggest you specify you want .002 shoulder bump to the brass guy on the next batch. This would give you a little clearance in the chamber and shouldn’t change anything about how the load performs but its your call.

Does the guy anneal your brass?

No, it wasn’t annealed.

 

[Multi-Tool]

Also, he said that he used a case gauge to check the headspace.

 

[nn8734]

Also, he said that he used a case gauge to check the headspace.

Hmmm. He may be referring to those check cylinders that you drop the case into. Id confirm with him but he should be using something like Hornady’s headspace tool to confirm his sizing die is set up correctly for your brass. Here is the Hornady tool I’m using to confirm bump on a 556 lake city case. I bump .004” for all semiautos…if hes not and you want him to bump your shoulders .002 or so, he wont have any idea how to set up that die.

This is why I do all this stuff myself.

 

[Multi-Tool]

The check cylinder was my impression too. The question mark in my mind is how “short” is the datum line measurement in a new .308 case vs. SAAMI spec? As I said, I have mostly loaded new brass for .308, so I am working my way through these issues.

 

[nn8734]

“SAAMI spec” in this context corresponds to the actual length of your chamber. In 308 Winchester, that length ranges from 1.630-1.634 depending upon what specific reamer was used on your rifle.

It’s also largely anecdotal for purposes of setting up the sizing die correctly. The hornady tool enables you to use the fired case to obtain your CH-shoulder reference measurement and use that to set up the die so that it bumps the shoulder back by whatever extent you want it bumped.

buy this tool along with a set of calipers so you can at least check his work by comparing sized cases to fired cases and see if they are sized as you want them. But honestly I’d start doing this stuff myself unless he’s doing it for free. Beyond that, he seems to be sizing with zero bump which for a bolt gun is fine until spring back appears after a number of firings and your resized rounds start to become difficult to chamber. That’s where annealing helps as it restores the brass to its original state from being work hardened as its being fired.