22lr AR-22/15 conversion issues

[gorillafingaz]

I just put together my first AR conversion. I am using tactical solutions bcg and black dog magazines.

Has anyone had problems with bullet tumbling?

I sighted in my aimpoint at 25 feet and was able to get three shots in a dime sized area. I figured I could put it out at 75 feet and get on paper and walk it in from there. What ended up happening was that I was all over the paper and could not get 3 shots in the same area.

I was shooting Remington thunderbolt lead ammo. I was also using a 1 in 7 inch twist 5.56 barrel. From doing some research, I found that there might be a problem with too much twist for such a small bullet.

Anyone else have thoughts on what I might do? Changing out the barrel to be a 1 in 9 twist and maybe go for a 20 inch barrel? I know the CMMG 22 conversion uppers use a 1 in 16 inch barrel, but I don't want to lose the functionality of being able to shoot .223/5.56 from the same gun.

Any/all help is appreciated!

[seal20]

What size dot on your Aimpoint?

What bullet weight?

The bullet drop should be the same at 25yrds as a .223. Also, how many rounds down the pipe?

When the barrel gets leaded up your accuracy will decline rapidly.

[2shotjoe]

That ammo sucks, try CCI

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[gorillafingaz]

Seemed like it started tumbling around 50 rounds down the pipe. This was only used to shoot 22lr, never shot any .223.

Aim point was a 2 Moa dot.

[BlairB]

I think the ammo is a big part of your problem (although probably not all of it). I went through a few hundred rounds of Thunderbolt today and the accuracy is definitely not the same as some of the higher end brands, and my .22lr AR really doesn't like it.

If you are considering getting a new barrel to better shoot .22lr out of your normal AR, do yourself a favor and just pick up a .22lr Barrel from CMMG and make yourself a dedicated upper. That is what I did and am much much happier.

Also, after you pick up that barrel and make a new upper buy a NFA complete lower and now you have a second AR! You are welcome.

[surplus-addict]

Okay, here's one of your problems...
You're firing a .220 projectile out of a .223 bore: it's not gonna be that accurate at long range.
And you also have a 1:7 twist! that's just begging for trouble.

The best thing you could do is build a cheap dedicated .22LR upper with blem/used parts and the cheapest 1:12 barrel you can find, maybe 1:9 if it's all that's available.

You can even plug the gas tube in the barrel since the .22 is a blowback round in this conversion. It would be a cheap, cheap upper to build, you'd probably no more than $150 if you watch what you're buying.

[Merc1138]

Okay, here's one of your problems...
You're firing a .220 projectile out of a .223 bore: it's not gonna be that accurate at long range.

Please go look up the bullet diameters for .22lr and .223/5.56. While you're at it, go look up .357 and .38 special as well. That way your mind will be blown twice.

Back to the OP...

You mention that the bullets are "tumbling", did you actually observe any keyholing on the target? Rounds striking the target sideways is kind of obvious, but you didn't mention that specifically was happening. As far as the aimpoint being a 2moa, or 4moa dot, that's a non-issue. If you can hold the top of the dot against the same portion of the target, it doesn't matter how large the dot is. If you're using a bullseye type of target with rings, it's actually really easy to center a dot within the rings even if it's obstructing your view of the center of the target.

You also said you couldn't get 3 shots in the same area and that you were all over the paper. What was the actual group size you were seeing? "all over the paper" could mean an inch or 5 inches apart to different people at 25 yards.

Yes, the twist rate isn't ideal. But you should try some different ammo. Rimfire guns are picky. You can get 2 guns from the same manufacturer, and find that they group totally different with the same ammo. BTW, modern remington .22lr ammo sucks balls for the most part.

The other thing to check would be the condition of the crown of your barrel. Take the muzzle device off, clean it, and check out the condition of it. Yes, a dedicated .22lr upper would probably be more ideal.

[frigginchi]

Get some 60gr Aguila SSS that stuff is tits in a 1/7.

[Furncliff]

Better ammo.

[NorCalDustin]

If you want more than just an inaccurate blaster... You kind of need a dedicated upper... Im not saying there aren't people who have accurate conversion kits, but generally they tend to be inaccurate unless your using really nice rimfire. --Which to me defeats the purpose.

[CWDraco]

1/7 twist
cheap ammo
conversion chamber
.223 exit bore

You should be able to hit a coke can, but I wouldnt expect any better accuracy past 50 yards.

[gorillafingaz]

Was thinking of getting a 20" 1x9 twist barrel. Then using better copper jacketed ammo.

[brassburnz]

I have an Olympic Arms 5.56 upper with a 1:10 twist and an M261 GI .22 conversion. Using Aguila SE ammo, this combo shoots sub-1 inch groups at 50 yards.

I think the 1:10 twist is the key to it's accuracy. You may have problems because of the twist rate of your barrel. Also, the longer 60 Aguila sub-sonic may help.

[shadow65]

Try better ammo.
While the 1/7 is not ideal, it should still give you 2-3" at 50 yards.
Get some CCI Mini Mags and see what you get.
Dave N

[CWDraco]

Was thinking of getting a 20" 1x9 twist barrel. Then using better copper jacketed ammo.

The 40gr .22lr expends all its energy at about 14" of barrel. After that you are just wasting energy on the rifling.

1x9 is really no better then 1x7, 1x10 and 1x11 are better and 1x16 is very good.

here, http://www.stevespages.com/page8e.htm use this.

there are no copper jacketed .22lr, its all copper plated, copper painted, copper washed, copper dipped. there might be some obscure .22lr FMJ, but I have never heard of it.