Set Headspace too far back on 5.56

[M-61]

Another way of asking the same question, how far out of battery when the cartridge fired?

Good question. My thoughts were that 'BELT' was not formed in the chamber. So I think I might be correct in saying whatever the length of the belt is should be pretty close to how far out of battery it was when it fired.
It's been quite a few years (10?) since this happened but both places I sent it seemed to agree that the forming of the belt could only be made by firing out of battery. Like I said its been a long time. Both places had no connection with Stag, powder, primers etc., so I thought it was an unbiased reasonable answers.
Plus over many years I have seen things 'mechanically' seeming impossible, happen.

 

[XTR]

223/556 cases seem to typically separate further up the case than 308s. Whereas 308 based cartridges tend to separate w/I about 1cm of the base the 223/556 variety seems to stretch and break about twice as far up the body.

yea, get a broken case tool and put it (them) in your range bag

 

[Metal God]

Am I the only one that looked at the two numbers in the OP and came up with a .010 difference and not the .003 stated ?

If he is at 1.445 but normally sizes to 1.455 ok that's .010 shorter but what about the .003 the 1.455 should be from his fire formed cases fired in the rifle ? My math says the OP is actually likely .013 short of his fire formed cases , that all assumes he bumps .003 and not more .

So I think .013 from fire formed is quite a bit and I’d put all that apply away for the zombie apocalypse and start anew .

 

[Twicepop]

If I read and understand your post, you pushed the shoulder back too far, been there/done that. What I did to save my brass was I used a Sinclair neck expander with a .24 caliber mandrel. I then re-sized the cases back down with the properly adjusted die creating a false shoulder to "head space" on.

 

[RegionRat]

Am I the only one that looked at the two numbers in the OP and came up with a .010 difference and not the .003 stated ?

If he is at 1.445 but normally sizes to 1.455 ok that's .010 shorter but what about the .003 the 1.455 should be from his fire formed cases fired in the rifle ? My math says the OP is actually likely .013 short of his fire formed cases , that all assumes he bumps .003 and not more .

So I think .013 from fire formed is quite a bit and I’d put all that apply away for the zombie apocalypse and start anew .

Agree with @Metal God , the numbers jumped up and I had to read this far down before it was mentioned as very odd.
Sure as heck needs another look to see if it was a typo or if was the actual values.

Many AR competition loads produce short brass lives even when everything else is done right, so you really have to study the case condition at the fourth cycle to see if it is time to retire the brass.