Anyone use IMR3031 with their M1A or other .308 gas gun?

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Cmeboston

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After some more testing I've found that 3031 out shoots 4895 in my new M1A. But I don't see it as a very popular powder in the M1A. Otis listed as being a fast enough powder for the gas system and doesn't require compression in military cases. Thoughts?

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Your experience mirrors mine. 3031 did better than 4895, 4064, W748, and H335. I used mostly Hornaday bullets, the 150 and 165 flat based were my favorites.
 
I have yet to try the others you have mentioned, and I did load up a batch of blc2 but I am hesitant to shoot it. I read anything faster than 4064 is bad for the gas system, although a friend with an Standard M1A swears by varget. I forgot to mention I have a scout with an 18" barrel


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You get with target shooters and they all have their favorite powders, and even though the 308 is no longer dominate on the firing line, most M1a shooters like IMR 4895 or IMR 4064.

The rule of thumb is not to use anything faster than IMR 3031 or slower than IMR 4064.

I used about two pounds of estate sale IMR 3031, found that it shot very well. I did not like the long grained structure of the powder, it did not throw as well as the shorter grained IMR 4895. It throws about the same as longer grained IMR 4064. Since I only weigh long distance loads, I use IMR 4895 for all my short range ammunition and most of my 600 yard ammunition.

It shoots well, so use it.

Code:
[SIZE="3"]M1A Super Match 1/10" 6 groove Douglas	second barrel

150 gr Hornady FMJBT 41.0 grs IMR 3031  Lot 385 Mixed LC WLR	OAL 2.785 
	 					
28 Sept 2008 T =  80 °F					
						
Ave Vel =2693					 
Std Dev =40					 
ES =126					
High =2747					
Low =2621					
N =14	

168 Nosler 40.0 grs IMR3031 wtd Lot FE23B LC90  CCI#34 	OAL 2.750"	
2-Feb-08	T = 52 ° F						
							
Ave Vel =2540					 	
Std Dev =42					 	
ES =101					 	
High =2585					 	
Low =2484					 	
N =5					

168 Sierra 40.0 grs IMR3031 thrown  lot FEB23B LC90 CCI#34 OAL 2.750"

18 May 2008 T =  71 °F		
				
Ave Vel =2533			
Std Dev =17			
ES =	45			
High =	2551			
Low =	2506			
N =	6		[/SIZE]

ReducedRightSiderifle1.jpg
 
I've used 3031 in two gas rifles and had very good results with it. Velocity was a bit lower at safe pressure levels than with 4895, but that's not really a major issue in a target match as long as the sights are dialed in for it.

On the other hand, I've snapped two op-rods with a recommended charge of 4064. Admittedly, it was on the upper end of the scale, and probably wouldn't have been a problem with a grain less...but the extreme spreads were a little wider than I liked when it was downloaded.
 
On the other hand, I've snapped two op-rods with a recommended charge of 4064. Admittedly, it was on the upper end of the scale, and probably wouldn't have been a problem with a grain less...but the extreme spreads were a little wider than I liked when it was downloaded
.


EEK! Snapped two operating rods.

I believe faster is better in the M1a and Garand in terms of powder. It is better to use IMR 3031 or IMR 4895 than IMR 4064 precisely because of lower port pressures. Lower port pressures are better for longevity than higher port pressure.

Faster is also better because aftermarket match barrels also have huge gas ports. It is not as if the GI gas port is too small, it diverts plenty of gas. Based on talks with one popular match barrel maker, he uses a commercial drill one size larger than GI. The GI port size is a non standard size, TRW could afford to have non standard drills made, but the smaller guys who make barrels, they are going to use what they can buy through a catalog.

And that is another reason to prefer faster powders than slower in a M1a.
 
Sounds good,thanks for the insight. the 4895 did well, but the grouping seemed a bit better with the 3031. This could have been the shooter considering it was my first really good day out with the scout. I usually weigh all my rounds, I use an RCBS uniflow powder measurer but find it to be inconsistent. But I don't know how much a half grain affects the round. Mabye I am being to precise? The listed data for 3031 only allows around 3 grains from start to never exceed. The data for 4895 is closer to 5. so it seems rather easy to overcharge with 3031. The reason I want to nail down a powder is i am running low and would like to buy bulk, and I certainly don't want to buy the wrong stuff. Anyone here recommend a. Good ball powder that meters well for plinking loads? I'd try a pound of that before I drop the cash on 8 lbs of 3031. My father said he used 4320 for his M1A, I tried it with my 30-06 Mauser and did not like it for Also should I even consider surplus powder? Or leave it alone. Thanks again guys,
John.


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