[oneshot onekill]

I just got a Supermatch M1A. I bought it used and I have a quick question. I have some knowledge of free-floating a Barrel and the effects of a barrel NOT being free-floated. On my Supermatch the Gas cylinder assembly lip is tight against the front stock ferrell. Thus rendering the barrel NOT free-floated. When I squeeze the barrel and the stock there is a space but when I let it go the barrel springs up and the lip catches the Stock Ferrell. Is that right? Or should the barrel float with a space between the Stock ferrell and the gas cylinder assembly lip? I would think it should float and perhaps someone didn't put the barreled action in the stock properly. I'd rather not remove it from the stock as I understand that damages the bedding... But if it's not put together right I need to fix it ASAP. Hopefully someone can clue me in.

Thanks in advance,
John

 

[dighawaii]

Aloha John,

Your barrel/front band to ferrule relation is as its supposed to be. There should be pressure on the front ferrule when you compress the barrel and the stock. I call it "draw" pressure.

There are lots of discussion related to draw pressure and the amount of draw pressure... also lots of discussion on how to achieve the desired draw pressure.

I remember that a couple of people actually tried "free floating" the barrel by removing the front band tab competely. From what I recall, it did NOT produce good accuracy.

My own experimentation has shown me that 30# of draw pressure gave me much better accuracy than 8# of draw pressure that was recommended in one of the books that I used as a reference.

Overall, I think if the SM was a factory SM, it should yield satisfactory accuracy. Again, there should be draw pressure and there should NOT have a gap between the front band and the ferrule.

I hope I was able of be of some help. Please let me know if I can elaborate on anything that I might have suggested.

Aloha and Good Luck,

Tom O.

 

[Col. Colt]

Your rifle is correctly bedded - the M14/M1A should not normally have a gap at the ferrule - and there must be tension there or the rifle will not shoot well. It is NOT a Bolt Gun and an entirely different animal.

Do some reading here in the NM/Accuracy Forums and you will find plenty of information on how glass bedding is done on an M1A, etc. Your rifle sounds fine - go shoot it and see how good it really is, I recommend you do your accuracy testing with store bought Federal 168gr. Match. Cheers, CC

 

[oneshot onekill]

Aloha John,

Your barrel/front band to ferrule relation is as its supposed to be. There should be pressure on the front ferrule when you compress the barrel and the stock. I call it "draw" pressure.

There are lots of discussion related to draw pressure and the amount of draw pressure... also lots of discussion on how to achieve the desired draw pressure.

I remember that a couple of people actually tried "free floating" the barrel by removing the front band tab competely. From what I recall, it did NOT produce good accuracy.

My own experimentation has shown me that 30# of draw pressure gave me much better accuracy than 8# of draw pressure that was recommended in one of the books that I used as a reference.

Overall, I think if the SM was a factory SM, it should yield satisfactory accuracy. Again, there should be draw pressure and there should NOT have a gap between the front band and the ferrule.

I hope I was able of be of some help. Please let me know if I can elaborate on anything that I might have suggested.

Aloha and Good Luck,

Tom O.

Mahalo Sir!

 

[oneshot onekill]

Your rifle is correctly bedded - the M14/M1A should not normally have a gap at the ferrule - and there must be tension there or the rifle will not shoot well. It is NOT a Bolt Gun and an entirely different animal.

Do some reading here in the NM/Accuracy Forums and you will find plenty of information on how glass bedding is done on an M1A, etc. Your rifle sounds fine - go shoot it and see how good it really is, I recommend you do your accuracy testing with store bought Federal 168gr. Match. Cheers, CC

Thank You... and I will get some Match ammo. I already tried her out yesterday with a few rounds my Brother made up some 10 years ago when he had an M1A. There weren't enough (only 10) for me to get a feel for the accuracy of my new girl. I'm also used to a 40X bolt-gun with a Mcmillan A5 Stock and about a 2 LB. single stage trigger so I'm going to need some trigger time to get her to group.

 

[30Caliber]

I think the M14 has too much hardware hanging off the barrel. You need that tension to dampen out all the odd vibrations you get when it all gets rung.

 

[M1AallTheWay]

I just got a Supermatch M1A. I bought it used and I have a quick question. I have some knowledge of free-floating a Barrel and the effects of a barrel NOT being free-floated. On my Supermatch the Gas cylinder assembly lip is tight against the front stock ferrell. Thus rendering the barrel NOT free-floated...

That is all true, and it's been my experience also that free-floating a barrel is a good thing.

However, as 30Caliber points out, even without the front band lip being hooked under the stock ferrule with draw pressure, the barrel is still not free floating. The resistance you feel when you start to pull the op rod handle back to open the bolt is pressing against the gas cylinder/piston when the bolt is closed and that pressure is being transferred to the barrel up front as well as changing the harmonics of the barrel once the op rod is fully forward. Moreover, there's enough slop in the movement of the op rod as it cycles that that pressure is not going to be 100% consistent in direction from shot to shot, so the pressure on the barrel up front is going to be in a slightly (and unpredictable) different direction each time. That's something the heavy barrel on the Super Match is more able to resist than a standard barrel, but for maximum accuracy, it's still an issue.

You may have noticed that the front band lip has a curve that matches the curve on the ferrule. The draw of the ferrule on the front band tends to make those two curves seek the most comfortable alignment at the front end (i.e., self-centering), which will be consistent from shot to shot if the bedding of the stock ensures that the receiver's position doesn't change in the rear end in the stock.

 

[oneshot onekill]

That is all true, and it's been my experience also that free-floating a barrel is a good thing.

However, as 30Caliber points out, even without the front band lip being hooked under the stock ferrule with draw pressure, the barrel is still not free floating. The resistance you feel when you start to pull the op rod handle back to open the bolt is pressing against the gas cylinder/piston when the bolt is closed and that pressure is being transferred to the barrel up front as well as changing the harmonics of the barrel once the op rod is fully forward. Moreover, there's enough slop in the movement of the op rod as it cycles that that pressure is not going to be 100% consistent in direction from shot to shot, so the pressure on the barrel up front is going to be in a slightly (and unpredictable) different direction each time. That's something the heavy barrel on the Super Match is more able to resist than a standard barrel, but for maximum accuracy, it's still an issue.

You may have noticed that the front band lip has a curve that matches the curve on the ferrule. The draw of the ferrule on the front band tends to make those two curves seek the most comfortable alignment at the front end (i.e., self-centering), which will be consistent from shot to shot if the bedding of the stock ensures that the receiver's position doesn't change in the rear end in the stock.

Ahhh... I see the truth of it.