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DaveN
03-06-2010, 10:38 PM
I checked hs on m1 w/ 1/2 muzzle and less then 1 on throat(from cmp)
and go and no-go were good. i used this as my bench mark. then i took hs on
2 ww2 receivered...1 sa,1wra, that had higher but not too high wear(m2,te3) the no-go
gauge allowed the bolts to close on both but it was not easy(some resistance)
i don't intend to fire these but could it be safe if i did. any info is appreciated as always.

JohnF
03-07-2010, 12:08 AM
I checked hs on m1 w/ 1/2 muzzle and less then 1 on throat(from cmp)
and go and no-go were good. i used this as my bench mark. then i took hs on
2 ww2 receivered...1 sa,1wra, that had higher but not too high wear(m2,te3) the no-go
gauge allowed the bolts to close on both but it was not easy(some resistance)
i don't intend to fire these but could it be safe if i did. any info is appreciated as always.

Both rifles are probably good to go, but check the headspace with a field gauge. If the bolt doesn't close on the field gauge then it's within SAMMI specs and safe to fire. If the bolt closes on the field guage then it is outside of the maximum chamber size and not safe to fire.

Punch The Clown
03-07-2010, 11:03 AM
I checked hs on m1 w/ 1/2 muzzle and less then 1 on throat(from cmp)
and go and no-go were good. i used this as my bench mark. then i took hs on
2 ww2 receivered...1 sa,1wra, that had higher but not too high wear(m2,te3) the no-go
gauge allowed the bolts to close on both but it was not easy(some resistance)
i don't intend to fire these but could it be safe if i did. any info is appreciated as always.

Dave, As John said you are good to go. If there was ANY resistance when closing on the no-go gauge that would mean the rifle passed.
The real decider on a used rifle is the field gauge but from your description passing the field gauge test is guaranteed.

us019255
03-07-2010, 12:13 PM
Grandpa Rudy was an old German trained toolmaker. He taught me how to use gauges in 1946. One always without exception uses all gauges with a gentle hand. If you apply force to a gauge you just accomplish two things. First, you put unnecessary wear on the gauge. Secondly, you spring or move the metal apart so that temporarily, you hope, the clearance has been opened up over what it really was.

The bottom line is that since the bolt does not close with an extremely gentle touch, you are below the NOGO size and thus good to go. If a bolt closes on a Field gauge, it is time to do something. Just like more oil or grease is not necessarily a good thing, trying to decrease headspace below the safe level doesn't do any good*. A NOGO gauge is meant as a specification during built or rebuild. The Field (some call it a field reject) means it is time for another rebuild.


In my personal case, if I were to force a gauge I'm sure that Rudy would come back from the grave and haunt me for the rest of my life.

*I'm not talking extreme target shooting here. The headspace for maximum accuracy with match ammunition is another subject, about which I defer to the experts.

DaveN
03-09-2010, 03:46 PM
thank you all for helping me, and the relief i have in knowing all is a ok.
and i will in future be gentle as a lamb. (though it was light resistance)