Unitizing the M1A Gas System


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Lazuris
July 31, 2009, 08:15 PM
Ok I've been dumping money into a loaded M1a trying to build the "simi auto percision rifle". It started life as a loaded M1a, I added a gen 2 J Allen some sadlak aftermarket parts, scope mount, gas piston, and spring guide. I'm getting 1" @ 100 with my hand loads but I don't think I've found the "load" yet. My gun smith recomends unitizing the gas system as a way to gain more accuracy from the rifle. I plan on installing a Krieger at some point but the current barrel still has alot of life on it. My smith has just recrowned the barrel as well and re-adjusted the muzle break.

So my question is what kind of accuracy does the unitizing result in?

I'm realistic as to what I can achieve with this platform but I would still like to improve on it if I can.

Please no comments on I should have gotten an Ar-10 clone and no I don't plan on buying a m-25/What ever H20 man has. I have what I have.

Thanks for your help guys.

Laz

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H2O MAN
July 31, 2009, 09:00 PM
I prefer shims. Just the thing for tightening gas cylinder and band between shoulder of barrel and gas cylinder lock. $15.00 from SEI

http://www.smithenterprise.com/imagesprod/2030.lg.jpg

LoneStarWings
July 31, 2009, 09:16 PM
You might consider a tubb's final finish barrel treatment if you really want to help. Chuck Hawk's seems to reccomend it, they got a 40% accuracy improvement from it on two different rifles:

http://www.chuckhawks.com/affordable_accuracy.htm

I don't know though, 1 MOA is actually really good if you can get that every time! My stock scout will do about 1.5 MOA 5-shot groups at 100 yards all day long with Fed GMM, occasional sub MOA groups and I'm pretty satisfied with that.

Other than that, bedding the stock and a trigger job seem to be the next big improvements!

What was your loaded shooting out of the box?

LoneStarWings
July 31, 2009, 09:37 PM
Oh, and from what I've read over at m14tfl.com unitizing the gas system is hit or miss. On some rifles it seems to shrink groups by 20-30%, on others it seems to make little to no difference. I guess the only way to know for sure is to do it yourself and find out!

Retro
August 1, 2009, 02:31 AM
I have done all of the above mentioned modifications, namely unitizing, Krieger barrel, JAE stock, sadlak piston, recoil guide rod, etc... I have found that the biggest problem with obtaining a subMOA group with a M1A is inconsistent shooting habits... And I have to say that M1A is much harder to shoot well than a AR10... It takes skill and a lot of practice to squeeze out the maximal accuracy out of a M1A. In light of this, many thinks it is also impossible to get subMOA accuracy out of a M1A system, at least on a consistent basis. I think it is one of the major reason that XM110 is gradually replacing M14 DMR as the DMR.

H2O MAN
August 1, 2009, 06:53 AM
Retro I have done all of the above mentioned modifications, ... I have found that the biggest
problem with obtaining a subMOA group with a M1A is inconsistent shooting habits

Yep, as with most firearms - it's shooting style, familiarity and muscle memory that results in the best consistent accuracy.

Even though I had a real nice AR-10A4 SPR with a SWS tube and a 2-stage match trigger, I was a
much better shot with my basic MK14 Mod 1. I replaced the AR-10 with another SEI built M14 :cool:

Lazuris, one additional modification I will suggest is SEI's M14/M21A5 C-IED 4.5 lb MAX-PAK Trigger Upgrade on a USGI or Chinese trigger group.
What Sadlak piston are you using?



.

Retro
August 1, 2009, 01:05 PM
Oh btw, I am yet to try M1A in a piston grip conformation. JAE stock is not quite a pistol grip because it didn't allow my fingers to close around the grip. I have heard that accuracy in a semiauto depends on whether you have a tighter hand grip on the stock.

H2O MAN
August 1, 2009, 04:26 PM
I highly recommend the SAGE Mod 1 (M14ALCS/CV) if you decide to get yourself a pistol grip stock.
The Mod 1 is easily two pounds lighter than both the Mod 0 SAGE and TROY MCS stocks and almost 3 pounds lighter than the JAE.

1st and 2nd generation Mod 1 stocks are pictured below and the plain black M14ALCS/CV is available for less $$.

http://www.athenswater.com/images/SAGE_Mod1_EBR-GenIandII.jpg

Lazuris
August 1, 2009, 05:17 PM
H2O MANI have the sadlak spring guide rod I believe they make only one type. And yes I would like to upgrade the trigger. I'm a big fan of smooth crisp triggers. For the record my current one is not bad. Almost no creap and it breaks reasonable well for a springfield.

I looked at tubbs but I'm going to reserve that as a last ditch effort. I'm not totally sold on the idea of shooting sandpaper from my rifle.

Retro What kind of accuracy are you getting with that setup. As I'm just a barrel and a unitized gas system away from your setup.

I guess my overall question is will I see an improvement in unitizing the gas system or is it just another part in trying to accurize the M1a?

30Cal
August 3, 2009, 01:39 PM
1MoA is about as good as it gets with an M14 type rifle. You can throw more money at it, but I doubt you're going to see much if any measureable improvement on a target.

H2O MAN
August 3, 2009, 02:42 PM
Lazuris H2O MAN I have the sadlak spring guide rod

Yeah, but you mentioned the gas piston... is it GI or aftermarket?

Sub MOA accuracy from an M14 rifle is no longer difficult, SEI's Crazy Horse rifles will shoot sub MOA.

30Cal
August 3, 2009, 04:59 PM
I'm highly skeptical of people who claim to have M14 rifles that shoot subMoA. I've seen it done from time to time, but never with regularity.

Five 10 shot targets fired on the same day would suffice as proof of a subMoA claim.

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