I have a Armscorp M1A and the headspace is just a touch too short. I was wondering if reaming it out a tiny bit would fix the problem. I know that usually you can not ream a M14 barrel because it is chrome lined but this has a USGI national match barrel which is not chrome lined. Any issues you can think of?

Yes it would. If you can get a "pull" reamer. These fit in the Garand or M1A chambers with a long extension through the muzzle. You GENTLY lower the bolt on the reamer and turn until the bolt goes into battery, then polish the chamber.

Thanks!

quote:

Originally posted by Masterifleman:
Yes it would. If you can get a "pull" reamer. These fit in the Garand or M1A chambers with a long extension through the muzzle. You GENTLY lower the bolt on the reamer and turn until the bolt goes into battery, then polish the chamber.

Wouldn't he need a pull through polisher?

Geoff, take it to a gunsmith and let him check the headspace using the appropriate gauge for either the 7.62 or the .308, whichever one the rifle is chambered for. Then if he needs to make an adjustment, he can remove the barrel, set the headspace using a lathe and polish it while it's in the lathe.

Pull through reamers are fine for military barrels but I would advise against using one in a match grade bore.

Geoff

Unless the reamer used to lengthen the headspace has the exact same diameters at the body and neck you could end up with "steps" in the chamber.

Unless the "short" chamber is causing problems I'd leave it alone. I'd guess that it is simply a minimum match chamber.

ray

quote:

Originally posted by Cheechako:
Geoff

Unless the reamer used to lengthen the headspace has the exact same diameters at the body and neck you could end up with "steps" in the chamber.

Unless the "short" chamber is causing problems I'd leave it alone. I'd guess that it is simply a minimum match chamber.

ray

It won't reliably chamber rounds the way it is. The bolt will only close on about 20% of rounds.

Hello,
Would ask if you are using new brass and if not, how many times has the brass been shot you are using?? Do you have a Moe's Gauge or the Stoney Point system to measure the dimensions of your fired cases in order to determine the chamber size?? Do you have Go/NoGo gauges??
Unerstand that you may not have these devices but using them will tell you quite a bit about the chamber issues. Years ago myself and others built routinely M1A/M14's to match std's and we had a selection of bolts to match up with the particular chamber on the barrel to obtain desireable headspace. I guess the bottom line questions is, are you resizing your fired brass to be somewhat less than your chamber size?? Moe's Gauge will tell you how much if any you need to bump back the shoulder of the brass to match or nearly match the chamber size. What is the mfg. of the bolt? Is it TRW, Win., SA or is it a "knock off" from China/Phillipines?? Don't mean to be preaching to you at all, just attempting to help and if you PM me I will provide you with a fellow's phone no. who still builds privately some of the best match grade M1A's available. He rufuses to believe that the AR15/16 platform will outperform his beloved M1A's for Across the Course style match shooting.

martin

The rifle started out as an Armscorp reciever and a USGI parts kit. I was able to get a Springfield Armory National match barrel and had my local guy install the barrel. The bolt is a TRW. I have a go guage and it just wont quite close on it. It also won't close on a commercial .308 round, and it will chamber an occational Port. 7.62 NATO or South African 7.62 NATO. I tried swapping bolts with 3-4 and this was the best one but still to tight.

Well, we do have a problem don't we. First off I would advise NOT to fire the rifle until the problem is solved. Perhaps you have not, but would not do so. If it will not close on Go Gauge, that is warning enough. Couple questions and no intentions of disrespect to anyone, but did the 'smith have experience in barreling M1A/M14's in the past?? If so, good, then the barrel itself is suspect. Perhaps the barrel was sold w/ short chamber, not finished to begin with and that is not uncommon for builders like to do their own final chambering for precision purposes. Was the barrel new when you bought it?? Tough to analyze from distance, but you may want to contact some of the High Power Shooters in your area/state for there are a fair number of excellent shooters from your state that participate in National Matches at Camp Perry and those who shoot the M1A would be able to direct you to informed members. Check w/ NRA web site for organized ranges in Mass. and go from there. Final question, have you shot the rifle at all?? If so, did it function, cycle, etc.?? Again, I would not fire the rifle until the issue has been resolved. Sorry could not be of more help. Take care,

martin

It was my understanding that it was a new never installed barrel from SA. I literally overlook the Springfield Armory from my office building so we see some uninstalled parts from time to time. The father of the dealer I bought the gun from actually worked at the armory. I think the barrel never had the headspace set so I think the pull through reamer is the ticket here.

And no I haven't fired the rifle as is.

OK, would say the chamber has not been final cut then and yes, "finish" reamer job should solve your problem. I would say that the installer should have caught the issue by checking headspace during the installation job?? Anyway, all's well that ends well.

martin