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CMMG .22 conversion

This topic can be found at:
https://sigforum.com/eve/forums/a/tpc/f/630601935/m/5380086274

July 23, 2020, 09:00 PM
Beezer
CMMG .22 conversion
Has anyone used or give any feedback on the CMMG .22 conversion kit. I am looking to add one to either a M400 Tread or a Tread Pistol.
July 23, 2020, 09:06 PM
RHINOWSO
I had one years ago, worked well but the twist rate from an AR isn't optimal so the rounds impact about 2 inches low at 25 yards.

Over time I sold it and moved to a dedicated M&P-15/22 setup for an "AR 22LR" platform.
July 23, 2020, 09:44 PM
hrcjon
are we talking the insert kit or an upper conversion kit, they make both. The latter is completely reliable. The former is not.


“So in war, the way is to avoid what is strong, and strike at what is weak.”
July 23, 2020, 10:11 PM
Beezer
quote:
Originally posted by hrcjon:
are we talking the insert kit or an upper conversion kit, they make both. The latter is completely reliable. The former is not.


I was referring to the bolt group kit. Not the complete upper. If you are saying the complete upper is better, I will look into that. Thank you.
July 23, 2020, 10:52 PM
hrcjon
The upper is totally mint. I have several and a zillion rounds experience. The bolt conversion insert is a bit more problematic. Depending on your goals the difference may/may not be something That matters since there is also a material price difference.


“So in war, the way is to avoid what is strong, and strike at what is weak.”
July 24, 2020, 12:10 AM
SIG4EVA
I have the conversion kit and it's great to plink with. I may end up making a dedicated 22 upper later but it's nice to have regardless.


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Psalm 118:24 "This is the day which the Lord hath made; we will rejoice and be glad in it"
July 24, 2020, 12:41 AM
1KPerDay
Love my stainless CMMG conversion kit. Works great in all ARs I’ve tried.


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July 24, 2020, 02:31 AM
Scott in NCal
I also have the conversion kit. Works great and is lots of fun. Also a AR equipped with the 22 Long Rifle conversion kit exempts the rifle from the California assault weapon ban.
July 24, 2020, 07:14 AM
Gibb
quote:
Originally posted by RHINOWSO:
I had one years ago, worked well but the twist rate from an AR isn't optimal so the rounds impact about 2 inches low at 25 yards.

Over time I sold it and moved to a dedicated M&P-15/22 setup for an "AR 22LR" platform.


I have both (conversion bolt and dedicated CMMG upper). I can hit the 8" steel gong at 25yds with the conversion bolt, but anything further out I have to use the dedicated upper for the increased accuracy.
The other thing I do is I always shoot a few 5.56 out of the regular bolt when I'm done using the conversion kit. I've seen people get their gas tube leaded up from .22lr rounds and have issues when converting back. So I shoot a few 5.56 when done to keep the gas tube clear.

I have used both with my Franklin Armory BFS3 triggers and they work great.

In short, if you just want a short range plinker for trigger time, get the conversion kit. If you want a .22lr AR, get a dedicated upper.




I shall respect you until you open your mouth, from that point on, you must earn it yourself.
July 24, 2020, 02:32 PM
kimberkid
I bought a CMMG upper for my M16, it took a bit of playing with it to get it reliable-ish with 22LR but in semi it never missed a beat.

https://www.youtube.com/watch?v=70PCPLmdeMk

I've also got one of their 22 bolt conversions, it pretty reliable but as mentioned above the bullet twist leaves something to be desired ... unless you can find an old skinny 1/12 twist, but IIRC the 22LR bullet diameter is slightly smaller than the traditional .223/5.56

The only down side to the CMMG upper, at the time I bought mine, you could buy a complete mid-tier AR, it was around $600, with the fullauto conversion ... this was when you could buy a "COLT" AR-22 for around $350.


If you really want something you'll find a way ...
... if you don't you'll find an excuse.

I'm really not a "kid" anymore ... but I haven't grown up yet either Wink
July 24, 2020, 09:56 PM
P210
Looks to be based on the old M261. Bought one of those new in the tube in the late 80’s and it worked well in semi. Never tried it in auto. I should dig it out and play with it again sometime. Apparently it was a good investment, considering what they’re going for now.
July 26, 2020, 09:31 AM
Expert308
A .22LR AR is one of the things on my "someday" list. I friend of mine has a conversion kit and it works great for him. Reliability has been great and accuracy is "good enough" for what he and his 12-yo son use it for (mainly blasting 8" or so steel targets in the 15-20 yard range. That said, when I get around to getting mine I'm planning on a dedicated .22 upper.
July 26, 2020, 12:08 PM
Ronin101
I like mine. never had any problems with mine. it shoots federal fine. But I often used mini mags.

Also it is good to shoot some 223 through it to blow out the residue from the 22's occasionally.

primary has a good price on tehm but they are currently out

https://www.primaryarms.com/cm...3-25-round-magazines
July 26, 2020, 02:37 PM
hudr
Back when I was thinking I’d have one or two lowers, and several uppers w/ different calibers, jobs, etc. , I had two. I never had any issues with either of them, in several different rifles.
But, once I bought an M&P22, I stopped using them.
One got sold, the other would be if interest was shown.
A dedicated .22 does work better.
July 27, 2020, 11:24 AM
Sigmund
This conversion kit gave me nothing but jams so I returned it.

https://www.brownells.com/rifl...7.aspx?sku=100010627

I found a great deal ($300 w/free shipping from CDNN) on a Colt Walther M4 which now has 200 flawless rounds through it.

https://www.brownells.com/fire...FF_22%2bLong%2bRifle
August 29, 2020, 07:40 PM
Beezer
I ended up picking up a Nordic Components 22LR 9.5” complete upper that is already threaded for a silencer that I have on order. Thanks everyone for your opinions it helped make my decision easier
September 04, 2020, 04:11 PM
Chowser
I had the conversion bolt and mags awhile ago and the rear of the bolt broke (the weld didn't hold). CMMG replaced the whole kit and I sold it. I then bought CMMG parts to build an upper and use S&W MP15-22 magazines with it with no issues.



Not minority enough!
September 06, 2020, 09:20 AM
Rob Decker
I HAD a conversion kit from CMMG that worked as advertised. Very reliable (aside from your occasional failure to fire because most .22 is crap these days) but, as other posters have noted, not all that accurate. Twist rate is wrong. Good if you only plan on shooting at a 25yd indoor range to practice handling or drills without chewing up a bunch of 5.56. The other downside is that the conversion kit will crap up your receivers with powder and lead fouling something fierce.

I wound up building a couple of dedicated uppers with CMMG kits. One was a gift and one I kept for myself. Mine went on a spare lower I had lying around. The barrel has the right twist and it groups a lot tighter than the conversion kit (though I haven't taken the time to bench it and shoot for groups, just rough zero from unsupported prone). You're still gonna get a lot of fouling but it's not as big of a deal, since you don't have to scrape it all out before converting back to 5.56 like you do with the drop in conversion kit. Bonus, standard aftermarket stocks, furniture, triggers, etc are all usable (my lower as an RRA Match trigger and it runs with the dedicated upper just fine).


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Death smiles at us all. Be sure you smile back.
September 06, 2020, 05:53 PM
air
I have the left hand version of the bcg, it works well with CCI. Same accuracy as others mentioned.

The chamber insert portion split and shaved lead to the point it fouled the chamber until it would not go into battery. CMMG fixed the bcg without hassle. I had to pull the barrel off to scrape and scrub the chamber and locking lugs clean of lead.


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