AR Rimfire Upper Accuracy - What are you getting?

[GN4HIR]

Guys, I'm sorry if this has been asked and answered. I searched and really didn't get the answer I was looking for.

Perhaps I'm spoiled. Off bipod/bags My 10/22 rifles and Savage bolt gun punch dime size holes at 50yds with Wolf and my Sig 522 will shoot an 1.5" consistently with the same ammo, sometimes better.

My new CMMG AR upper won't do better than about 3" and I tried 5 or 6 different brands of ammo. Is this just the nature of the AR rimfire upper?

I got the AR upper because I wanted to chop the barrel and drop it on my SBR lower but I expect something close to my Sig 522 in accuracy.

 

[HPLLC]

Re: AR Rimfire Upper Accuracy - What are you getting?

I had a DPMS upper (dedicated) and it was grouping ~5/8-3/4" at 50 yards. Really an accurate little settup.

 

[frog5215]

Re: AR Rimfire Upper Accuracy - What are you getting?

Free float.
Try removing the flash suppressor, the .320" flash suppressors don't some shoot well.
My Lother Walther shot 5/8 to 50yd (SK, RWS). With .45"after reaming, to .335-.40.

 

[CSS]

Re: AR Rimfire Upper Accuracy - What are you getting?

When I was sighting in my Tacsol LW upper and trying a few types of ammo, SK/Wolf was well under an inch at 55yds.
This was with proping my elbows on a bench, no rest or bags and a RRA 2 stage trigger.

 

[GN4HIR]

Re: AR Rimfire Upper Accuracy - What are you getting?

I think I will give the free float a try and see if that helps. I was shooting off a sand bag and who knows if that would induce enough tension to upset groups.

Anyone else shoot a CMMG upper that would care to speak up.

 

[Outdoorsman9]

Re: AR Rimfire Upper Accuracy - What are you getting?

I get about 4-5 inch groups at 100 yards with my Nordic Components upper. Mine is the one with the 18" barrel. I've tried multiple types of ammo but they all basically grouped similar.

 

[rich56]

Re: AR Rimfire Upper Accuracy - What are you getting?

my Nordic .22 upper on a Rock River lower got about 5/8-3/4" @ 50yds with CCI and Federal standard velocity ammo with 100% reliability. 20 inch standard barrel

 

[Hellbender]

Re: AR Rimfire Upper Accuracy - What are you getting?

<div class="ubbcode-block"><div class="ubbcode-header">Originally Posted By: jiwilliams</div><div class="ubbcode-body">
My new CMMG AR upper won't do better than about 3" and I tried 5 or 6 different brands of ammo. Is this just the nature of the AR rimfire upper? </div></div>

It's not the nature of AR rimfire uppers, it's the nature of CMMG AR rimfire uppers.

I have had/have several TacSols, 2-CMMG, and CLE, both CMMG were about 3-5" at 50 yards, the others are all under an inch, some well under.

My conversions kits shoot better than that with .223-7 twist barrels.

 

[GN4HIR]

Re: AR Rimfire Upper Accuracy - Update

Ok, here is an update.

First the bolt / collar / barrel is a bit FUBAR. Typical headspace for 22 is something like .042 or .043, this bolt is .048. Ok, that in itself isn't too bad; however, the barrel face is recessed .006 from the collar and because of the ramp the bullet is extending out of the chamber by .020 or so. See the picture. I have not decided if I just want to send it back or get the dremel out and try to fix it.. (dremel usually means complete FUBAR).

Now, even with the chambering issue, I still decided to try shooting it with a free float handguard and yes, the groups improved a great deal. Wolf is still the best group and it was shooting about 2" at 50 yds; however, I had several failure to fire which I strongly suspect are caused by the fact the case head is not up against the barrel face and therefore the firing pin is not getting a solid hit.

 

[HPLLC]

Re: AR Rimfire Upper Accuracy - Update

DO NOT DREMEL.

Send the bastard back. That's the only guaranteed outcome. If you dremel and screw it up, they will probably not replace or fix the barrel.

 

[frog5215]

Re: AR Rimfire Upper Accuracy - Update

Send it back.
CMMG will fix it.

 

[GN4HIR]

Re: AR Rimfire Upper Accuracy - Update

Agreed.. I'm dangerous with dremel. Spoke to Chris at CMMG and he said they would take care of it and get it working properly.

 

[67rschev]

Re: AR Rimfire Upper Accuracy - Update

1 inch at 50 with a Tacsol LT and assorted bulk ammunition

 

[ggmanning]

Re: AR Rimfire Upper Accuracy - Update

Nordic 16" upper on a RRiver lower getting about 3/4-1" or so at 50 with Wolf match and CCI subsonic. That is with a 1-4 SS so it might do better with more mag but I have never tried it. I have only shot it with a supressor and it is a good shooter. It is solid drink can accurate at 50 and that is good enough for me and how I use it. 100% reliable as long as I keep it clean with the suppressor.

 

[msflyer]

Re: AR Rimfire Upper Accuracy - Update

I also have a cmmg that was shooting poorly. After about 300 or 400 rounds it got a good bit better. After switching to the cci AR 22LR copper plated ammo, it got a lot better. Typically 1.5"-2" groups at 100yds with maybe 1 flier out of 6. Things really changed after around 400 rounds. Still, if going back in time I'd probably wait for a Nordic or TacSol, but for what I paid...I'm happy.

 

[cj johnson]

Re: AR Rimfire Upper Accuracy - Update

i have the m&p version and i was really suprised how i would get 3/4 inch groups at 50 yards then have 2 or 3 fliers in a row and i was using a bipod on mine. not very impressed by the accuracy. did expect more.

 

[cmh2007]

Re: AR Rimfire Upper Accuracy - Update

between .4 and .5moa right now. but doing a bedding job on the rifle now and hoping for better. also going to do a trigger job to see if it makes it better

 

[PowerstrokeOBX]

Re: AR Rimfire Upper Accuracy - Update

<div class="ubbcode-block"><div class="ubbcode-header">Originally Posted By: seaaggie</div><div class="ubbcode-body">between .4 and .5moa right now. but doing a bedding job on the rifle now and hoping for better. also going to do a trigger job to see if it makes it better </div></div>

Bedding on an AR?