AR groups wandering. Most likely fix?

[WillaminaOR]

Picked up a new to me upper. Found I don't shoot those iron sights very well any more. So I took a scope off another rifle and put it on. Went and checked I'd be on paper at 25Y, group wasn't very good even at 25. CBC m193 ball ammo. Backed the target off to 100 and shot a control group out of my other gun, 5 shots about 2" with a 4x scope and the same ammo. Not to bad with cheap fmj. So I had 10 rounds left in the rifle with the new to me upper, slowish aimed fire, the group is in a diagonal string, 4-5 inches long. I'm not 100% sure they were the last 4 shots but 4 of the last 4-5 shots fired are about touching. 20" BHW, rifle gas, free float tube. Could this be receiver fit? Something weird with the gas block and tube?

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[CLee0507]

That's consistent with M193. Get some Federal Premium 69 or 77gr Sierra match. That is of course your scope is tight, you could also check barrel nut.

 

[Member 5605]

Small-bore Shooting - Group diagnosis - by W.H. Fuller

Historic Arms Resource Centre facility for British and Commonwealth Enfield and other Miniature calibre training and small-bore TARGET RIFLES (BSA- Birmingham Small Arms Co.), conversion units and accessories with representation of other nations' training rifles, plus Postal League competitions...

www.rifleman.org.uk

Slanted shot strings are a pattern. Near bottom of the above link you can find some solace. "Figure #8"

The rifle should shoot about 2"-4" groups with ball ammo.

I ran that same pattern down left, up right with a new rifle until I realized what I was doing wrong, I was shooting .22LR from a match rifle at 50Y and my pattern string was about 6" diagonal.

 

[MrMillspecer]

I would try some other ammo. It may like something heavier than 55g. Shooting at 100 yards with a 4x scope I have a hard time keeping it on target. What's the twist ? Scope mounts good and snug ? Wind ?

 

[ma96782]

BUT, But, but....
Most everyone (on various forums) claims to get 1" groups at 100 yards with their AR?!?!

Rrrright.......

Aloha, Mark

 

[MrMillspecer]

BUT, But, but....
Most everyone (on various forums) claims to get 1" groups at 100 yards with their AR?!?!

Rrrright.......

Aloha, Mark

Heres a $500 Delton kit AR at 100 yards. It didnt like my 69gr reloads. I was using more than a 4x scope.

 

[ma96782]

Never mind the other groups. BTW.....I once shot a 100 yard, 1" group with my M1a with iron sights. But that happened only once.

Aloha, Mark

 

[WillaminaOR]

I would try some other ammo. It may like something heavier than 55g. Shooting at 100 yards with a 4x scope I have a hard time keeping it on target. What's the twist ? Scope mounts good and snug ? Wind ?

Shooting at 100 with the 4x netted me the 2" 5 shot group, out of my other rifle. Shooting the larger diagonally strung group was at 100 with a 12x on the rifle I'm questioning. Mount was torqued onto the receiver to 20in lbs. There was some wind but I don't think it was enough to account for that much spread.

Bryan

 

[Member 34319]

Put the same ammo through a chronograph.

If the spread is more than 100FPS I'd say it's the ammo.

As many have already said, buy and try some better ammo.

 

[WillaminaOR]

I'll probably load something up. Just been feeling really lazy. I did set myself a goal of developing an accurate load for my rifle so I could crank out a bunch of them. Of course that was thinking of the other rifle with the 4x scope. There's just a lot of steps involved with getting raw once fired LC brass ready. I wonder if I'll find a load that's accurate in both barrels?

Bryan

 

[TTSX]

BUT, But, but....
Most everyone (on various forums) claims to get 1" groups at 100 yards with their AR?!?!

Rrrright.......

Aloha, Mark

The only gun I've personally witnessed legitimately being MOA or better is my Savage model II. Everything else is roughly fist sized at 200. But you just gotta let people believe what they wanna believe

 

[v0lcom13sn0w]

the most likely fix?


shoot better.





jk. id be happy with those groups with xm193 ammo.

 

[WillaminaOR]

the most likely fix?


shoot better.





jk. id be happy with those groups with xm193 ammo.

2" 5 shot group I'm pretty pleased with. And to me, kind of shows the ammo isn't all that bad. 5" 10 shot group, I'd sure hope for better than that. I'll try to get over my lethargy and go make up a batch of handloads.

Bryan

 

[v0lcom13sn0w]

2" 5 shot group I'm pretty pleased with. And to me, kind of shows the ammo isn't all that bad. 5" 10 shot group, I'd sure hope for better than that. I'll try to get over my lethargy and go make up a batch of handloads.

Bryan

let us know what you come up with!! ive had pretty good luck using IMR4320, h335 and blc2 for 5.56 handloads!

 

[WillaminaOR]

let us know what you come up with!! ive had pretty good luck using IMR4320, h335 and blc2 for 5.56 handloads!

I've had good luck with BL-C(2) in the past but wanted to try something that's supposed to be more temp insensitive. I've got a couple lbs of Benchmark in going to be using. Gonna try some bulk 55gr Hornady, Hornady Zmax that are acclaimed for their accuracy, and maybe for chasing groups I've got some different OTM bullets. I guess I'll try this upper as is with some handloads held to decent standards, see what happens.

Bryan

 

[wordsmith]

Picked up a new to me upper. Found I don't shoot those iron sights very well any more. So I took a scope off another rifle and put it on. Went and checked I'd be on paper at 25Y, group wasn't very good even at 25. CBC m193 ball ammo. Backed the target off to 100 and shot a control group out of my other gun, 5 shots about 2" with a 4x scope and the same ammo. Not to bad with cheap fmj. So I had 10 rounds left in the rifle with the new to me upper, slowish aimed fire, the group is in a diagonal string, 4-5 inches long. I'm not 100% sure they were the last 4 shots but 4 of the last 4-5 shots fired are about touching. 20" BHW, rifle gas, free float tube. Could this be receiver fit? Something weird with the gas block and tube?

View attachment 698028 View attachment 698029

I have found there are 3 things that you should consider for consistent accuracy - rate of twist (bullet weight), optics and trigger. I have an AR with a Davidson Defense forged upper with an XXtreme barrel chambered in .223 Wylde with a 1 in 7 twist, a Nikon 3X9 BDC scope and a CMC 3 lb. match trigger. I normally shoot 500 - 600 rounds per week, weather permitting. I mostly use inexpensive steel cased Tula .223 ammo. With 62 grain hollow points it averages 2850 - 2860 FPS. From a bench I average 1 1/2" to 2" groups at 150 yards. I suggest you check your rate of twist to determine the proper bullet weight. If it's a 1 in 9 or a 1 in 8 twist shoot the lighter bullets - 55 to 62 grain. If your twist rate is 1 in 7 shoot 62 grain or heavier. I would also suggest a trigger upgrade. There's no reason an AR shouldn't print 1" groups at 100 yards if it is set up properly. Hope this helps.

 

[CLT65]

BUT, But, but....
Most everyone (on various forums) claims to get 1" groups at 100 yards with their AR?!?!

Rrrright.......

Aloha, Mark

I wondered if I was the only one who noticed that. They always claim to shoot 100 yard MOA groups, with cheap, off the shelf ARs and bulk FMJ ammo, but it's always with the magic words: "All day long" and "as long as I do my part".

Then there are all the internet commandos who claim to be able to shoot 1/4 moa on demand. If you can occasionally shoot a 1/4 moa group, congratulations! You're probably a great shot with a darn good rifle. If you can do it consistently, you don't need my congratulations. You already know you're a helluva shot, with an expensive rifle and a lot of practice! If you tell me you can do it "all day long" with your favorite dear rifle, and you're not a bench-rest competitor... Rrrright

 

[HA556]

If you tell me you can do it "all day long" with your favorite dear rifle, and you're not a bench-rest competitor... Rrrright

Come on man, you know those living in Momma's basement, no job, pizza eating Halo Commandos can do most anything!

 

[MrMillspecer]

If you ever used an upper from White Oak Armament on a AR15 you would realize 1" groups come easy. Yes I have one.

 

[osprey]

Were those shot right in a row? What is the barrel contour? Could be walking the poi as barrel heats up. Factory upper? Who built it. Plenty uppers out there that will shoot sub 2" 10 shot groups or better.