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- #41
Yeah, the first Scout I saw was in a flimsy synthetic stock, so I had them find me one in walnut, potentially better for accuracy.
What's Your Experience in Accurizing an M1A?
- Thread starter nortac
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- #42
Well I had a frustrating range session yesterday with my M1A. I managed to eliminate the contact between the stock channel and the op rod guide and saw no further evidence of any contact between the stock ferrule and the gas cylinder. In an attempt to gain the proper tension between the barrel band and the ferrule, I placed some HVAC aluminum tape shims between the front edges of the receiver and the top edge of the stock. It worked, sort of. But it is only a temporary solution, it will eventually need to be glass bedded to achieve a permanent solution. The initial net result was a shift in POI of about 4 in. high and 2 in. left of my previously dialed in scope settings! Arrgh! The aluminum tape shims proved to not be very stable and in retrospect took a lot of shooting to settle in, as I seemed to have had wandering POI through out the shooting session. I did not have a chance to do any reloading prior to this range trip and shot only factory ammo. This gun doesn't seem to like the Federal Lake City XM80C 149 gr FMJ, the best I could get with it was a 2.5 in. group. The gun seems to like Federal Gold Medal Match 168 gr better and FGMM 175gr. even better still. I ended my shooting session firing a 15 shot group. The first 8 rounds clumped into about an 1.25 in. cluster. Then the remaining rounds jumped about an inch and a half to the right and formed a very tight vertical string with several rounds touching! In this instance I think the vertical aspect was definitely from barrel heating, (note how the quote from Rob and the M14 forum describes a tight vertical string), but the sideways shifting of the group must be from my improvised shim job readjusting itself!? One shot was unaccounted for, who knows what happened to it.
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- Thread starter
- #43
I've gotten a few compliments at the range on the wooden stock. It's not fancy grained and has a dull finish, but wood appeals to those of us who weren't weaned on synthetic stocks.
I'm sure it also tames that short barrel much better than synthetic too.
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- #45
No doubt. I have yet to shoot it off hand much. It will be interesting to see how it performs shooting off hand at engaging multiple targets rapidly. When I finally get it tuned in and set up the way I want it, I may have to take it to a three gun match for S&Gs. Won't be competitive with the ARs and such, but I never shoot for scores in those types of matches, just for tactical reality if possible.
Question: Have you closely inspected the crown on your barrel? Might want to keep your group count to only 3 shots per group while adjusting things. It will conserve ammo and take barrel heat out of the equation.
That's a pretty decent group so far. Even the pairs in your string are touching. Account for drop and creep and you will be on your way. Again, i'm no expert in anything, but it just appears to be a harmonizing issue like barrel whip. Pretty common occurrence in heavy, short barreled production rifles.
http://www.stocks-rifle.com/harmonics.htm
https://www.shootingsoftware.com/barrel.htm
And of course you realize, that out of the three different velocities of the rounds you have been using, you will get completely different patterns from that type of barrel? The heavier slower rounds of the match grade you are currently using, will of course exit the barrel slower, so the barrel's vertical swing will be much higher.
So when that slow bullet finally exits the muzzle, it will launch at a different and higher angle than some of the other rounds you have used already. Because the round is heavier and slower, it will definitely drop more than the other variations of loads, weights and velocities. I know it can become very frustrating, chasing the accuracy for a rifle and it's ammo at the same time.
Trust me, been there done that.
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- #48
Rob, I have not inspected the crown, the muzzle brake hides it, but I could peer in there with a light, I suppose.
I do realize the different bullet weights will have different trajectories, not too worried about where they will strike on the target at this point, only the group size and consistency for now. I will eventually settle on a bullet weight and actual sight in. I will try some Hornady 168 gr. TAP as a "bidness" round and develop a handload to duplicate those ballistics once everything gets tuned in. I have been shooting the 150 or so gr. bullets just for the brass, especially the Lake City brass.
I do realize the different bullet weights will have different trajectories, not too worried about where they will strike on the target at this point, only the group size and consistency for now. I will eventually settle on a bullet weight and actual sight in. I will try some Hornady 168 gr. TAP as a "bidness" round and develop a handload to duplicate those ballistics once everything gets tuned in. I have been shooting the 150 or so gr. bullets just for the brass, especially the Lake City brass.
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- #49
Put a custom 20" on it. You'll compete.
Not an issue of barrel length/accuracy, but of shot to shot times and recoil recovery. If I were gaming the match, the thing to do would be to load 110 grain bullets with a reduced load (adjustable gas nut would come in handy here). Magazine changes would be a lot slower with an M1A compared to an AR as well. But again, I'm not about scoring high in a match these days, just in keeping it real with regard to tactics. Plus I don't move as fast as I yuse to! LOL!
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- #50
Barrel crown looks fine, shining a light down the flash hider. Wouldn't expect a problem with a new gun, but you never know.
Understood. That's why I said in a earlier post, your initial group before the barrel heating up looks good. You did say that you are throwing them out of the gun pretty fast?
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- #52
I still think the high shots in the first target that I posted were due to the op rod guide bouncing off of the stock barrel channel rather than barrel heating. The last target posted was most likely due to barrel heating because:
1) I had further relieved the barrel channel since shooting the first target posted and there was no evidence of contact with the op rod guide after shooting the second target posted.
2) I shot a longer string faster than those fired for the first target and the tight vertical pattern vs. the random nature of the first target.
The way 6 of your first 8 shots in that group are stacking, it appears you have timing and recovery figured out.
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- #54
Nooo.. shooting from the bench at a leisurely pace is one thing, shooting on the move and rapid target acquisition is quite another!!
I wanna rock this badboy! Hit and git!
Lol'd!
I do not own an M1A1, but I have known a couple serious competitive shooters who have both told me that these are very difficult to accurize compared to (e.g.) an AR15.
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- #57
I knew going in that the M1A would never equal the potential accuracy of an AR, it is not my intent to turn this particular rifle into a target gun, but rather a practical major caliber carbine. I will be happy with 1.5 MOA and I think that is very doable.
Shorty Battle Rifle.
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- #59
Intermediate Barrier Defeater.
Qft
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