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Discussion Starter · #1 ·
Well men, and ladies.......Doc stopped by again this afternoon and brought a real nice specimen. An early Armscorp with serial # 16XXX and it needed the magic touch and going over, just for safety sake, and his peace of mind.....this ,because the last two early Armscorp rifles he brought over had tight headspace, so we decided to check every rifle he owns.....wow, what a can of worms I opened...my idea....ha ha ha.....I love it though.

Back to the inquiry...I need to know how many of you have all G.I. parts Armscorp rifles with G.I. barrels, and if you know the headspace, what it is , especially with the TRW barrels.

Out of his first three, all TRW rifles with TRW barrels and TRW bolts, the headspace was :

1st one- 1.630

2nd one- 1.628

3rd one- 1.630

I must note also that all bolts were in spec.

If you do own one of these Armscorp rifles as described above, it might be a very good idea to have your headspace checked. Actually, anyone that doesn't know their rifles headspace, is playing Russian Roulette.

Post em if you got and please help me figure if this is an anomaly or the usual for Armscorp. Also if you had one and found tight headspace previously, thanks,... rip.
 

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All 3 are minimum to barest minimum for .308 Win, below minimum for 7.62 x 51 NATO. I'm surprised considering the USGI barrels.
 

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Armscorp serial number 173XX, TRW chromium plated barrel, Winchester bolt, 1.630 " headspace
 

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Wouldn't headspace be more a product of the smith that built the rifle than the manufacturer of the reciever (assuming the reciever was built to within reasonable spec)?

I would also inquire as to how many of the barrels had been previously installed and were take offs (rolled shoulder?) and how many were NIW/NOS?

Assuming this is true then I would ask the important question....who built each of the rifles in question?
 

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i bought one years ago

i bought my 16xxx years ago. assembled by a navy armorer. TRW barrel and bolt. short on headspace when i got it, below 308 go. i lapped bolt nto rcvr. and removed nearly .001 from bolt face to correct. it is now between 1.634 and 1.638. i have shot several thousand through it since. it is my go to rack grade rifle.
 

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I have an ArmsCorp from 1994 all USGI parts with a TRW barrel. I do not have any means to check the headspace. As far as I know there are no competent smiths close to where I live. ( Valrico, Florida) where I can bring it in and have him check it while I wait.
The rifle was assembled by ArmsCorp and headspaced at the time of assembly.
How important is this for me to do it at this time?
How expensive is it to buy the gauge's and do it your self.
How many gauges would I need?
Any information on this would be appreciated.
 

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Discussion Starter · #7 · (Edited)
The go gauge for S.A.A.M.I. is 1.630 minimum headspace and cost about $27....it is a must for any owner of these rifles.

Check with Brownells, or Pacific Tool and Gauge, or Clymer Tools........One gauge, the Go, will suffice for now and safety, but for mil-surp you need around 1.632 to 1.633 for worry free shooting....

If you buy a go gauge at 1.630 and read Gus Fishers thread all about headspace in his forum here, and practice it till you get confident and know its right, then you can get a rough estimate with a piece of scotch tape taped to the back of the go gauge, which is roughly .002 thick, if you know what you are doing and don't smash it with interferance fit or friction fit......Trim the tape off the back, even with the edge of the gauge too, with a knife or razor blade. This added with the 1.630 will tell you if it is close to 1.632....read Gus's thread at least 2-3 times and understand it first.

I would eventually get more gauges if you have any amount of rifles at all and shoot them regularly. It is a good idea to check headspace every so often to keep an eye on it. I don't know the validity of the story, but had a guy tell me that one fella got a chinese rifle and checked headspace, fired about twenty rounds, and checked headspace again because he had problems and thought he did it wrong. The soft bolt and/or receiver had allowed the headspace to open up over .002 in that few rounds.....

If you shoot mostly mil-surp Nato ammo, then minimum is too tight to not cause problems eventually....especially after the chamber gets dirty from firing. Then cases will get stuck, or you can have bottleneck blow outs or caseheads ripped off them....Not good...... The pressure increases in the chamber are not the least of these problems, caution is advised.
 

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Armscorp Head Space

While Armscorp wasn't too fussy about the head space when assembling their rifles, the head space was kept within necessary specs.

Seemingly short head space in the 1.630" range is fine for .308 Winchester. Some NATO spec ammunition may not chamber completely in chambers this short.

It is the obligation of the gun smith to insure that head space is within safe specs, but chrome lined barrels don't always allow adjustments to chamber depth. Special reamers are required. Minimum head space in chrome lined barrels is allowable, but one must keep in mind that there may be some ammunition that won't allow the bolt to close fully in this situation. For this reason, head space in the 1.632" to 1.634" range is prefered. Longer head space to 1.640" is still safe and acceptable.
 
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