Welding Rod
Member
I have a SA Standard M1A. It was built in 06 or 07. I bought it new. It has approximately 2-3 hundred rounds through it. It has only been shot with factory ammo. The gun is completely stock.
There was a SA slip that came with it that noted the headspace was set at 1.631", that is one thousandth above minimum.
Today I was gauging some brass for headspace with my RCBS Precision Mic. I believe my the gauge to be accurate as most unfired factory ammo is gauging from the .308 maximum allowed dimension at - .002" to .000".
Brass fired through my Ruger Hawkeye .308 is gauging + .001" to +.002" after firing.
Brass fired through my SA SOCOM is gauging +.005" to +.007" after firing.
But brass fired out of my SA Standard is gauging +.013 to +.015" after firing.
This is with a couple of different commercial US .308 loads and South African FMJ.
I have checked to make sure there is no primer protusion or burrs on the case head before measuring.
Now an odd thing is this stretched brass that comes out of the Standard will not rechamber back in the same gun. The bolt will not go forward enough to allow it to rotate into battery. I guess that is the good news. Maybe the headspace is OK afterall (?).
So any idea what is going on here? Why is the brass being stretched so much? Can I prevent this? I would like to be able to reload the brass, but that level of stretching seems really excessive.
There was a SA slip that came with it that noted the headspace was set at 1.631", that is one thousandth above minimum.
Today I was gauging some brass for headspace with my RCBS Precision Mic. I believe my the gauge to be accurate as most unfired factory ammo is gauging from the .308 maximum allowed dimension at - .002" to .000".
Brass fired through my Ruger Hawkeye .308 is gauging + .001" to +.002" after firing.
Brass fired through my SA SOCOM is gauging +.005" to +.007" after firing.
But brass fired out of my SA Standard is gauging +.013 to +.015" after firing.
This is with a couple of different commercial US .308 loads and South African FMJ.
I have checked to make sure there is no primer protusion or burrs on the case head before measuring.
Now an odd thing is this stretched brass that comes out of the Standard will not rechamber back in the same gun. The bolt will not go forward enough to allow it to rotate into battery. I guess that is the good news. Maybe the headspace is OK afterall (?).
So any idea what is going on here? Why is the brass being stretched so much? Can I prevent this? I would like to be able to reload the brass, but that level of stretching seems really excessive.