CMMG 22lr conversion kit questions

The Best online firearms community in Louisiana.

Member Benefits:

  • Fewer Ads!
  • Discuss all aspects of firearm ownership
  • Discuss anti-gun legislation
  • Buy, sell, and trade in the classified section
  • Chat with Local gun shops, ranges, trainers & other businesses
  • Discover free outdoor shooting areas
  • View up to date on firearm-related events
  • Share photos & video with other members
  • ...and so much more!
  • bush_hog

    Well-Known Member
    Rating - 100%
    49   0   0
    Jul 8, 2007
    863
    18
    Covington
    Hey guys. I'm sure some of you have crossed this bridge a time or two... with respect to the CMMG conversion bolts and magazines that you can buy as a kit...
    how well do they work ?
    how dirty do they make your 5.56 upper ?
    does the lead build up too much in the barrel or gas block port ?
    is it a better idea to just build a dedicated .22lr upper ?

    I'm mainly looking to do more paper shooting drills and think that .22lr fire will be more welcomed by the neighbors than 5.56 fire...

    I'm after more real results than internet star reviews / commentary.

    Thanks in advance for your constructive input!
     

    thperez1972

    ESSAYONS
    Staff member
    Gold Member
    Rating - 100%
    10   0   0
    Dec 28, 2015
    5,713
    113
    Baton Rouge, LA
    Are you referring to the full dedicated 22 parts or the "shoot 22 out of a 223" adapter that only replaces the bcg? I'm guessing you are talking about the adapter. I have a dedicated 22 pistol build and an adapter in a full size rifle. They both work well although I haven't put the number of rounds though it one would with proper rifle drills. The insert was for a young one to get used to the rifle itself before switching out the bcg to upgrade. And the pistol is more of a novelty as it's got a 4" barrel and no buffer tube.
     

    340six

    -Global Mod-
    Staff member
    Premium Member
    Rating - 100%
    5   0   0
    Apr 12, 2012
    6,499
    113
    Kenner, La
    I do not have one yet but after seeing number of threads on this, I made up my mind to get a dedicated upper.
    I do have a pile of Sig and Black Dog Mags.
    I keep putting it off though since a,have a Sig 522.
    I do not want to put a pile of dirty 22lr in my 223 upper.
     
    Last edited:

    themcfarland

    tactical hangover
    Rating - 100%
    58   0   0
    Dec 6, 2008
    4,656
    63
    Destrehan
    The BCG with chamber adapter is the best conversion next running a dedicated upper.. I have both.. it comes down to 1x7 twist is not the best for even 40gr bullets but 1x8 and 1x9 does OK.. dont expect MOA at 50 yards.. even with a dedicated upper.. but its more reasonable if you just want to get kids involved or inexperienced shooters to use a full size gun with less report.. get the chamber adapter.. be sure to check the orings for good seal.. also expect to clean the upper more, but at least lube it well..
     

    bush_hog

    Well-Known Member
    Rating - 100%
    49   0   0
    Jul 8, 2007
    863
    18
    Covington
    So I bought the CMMG conversion kit a while back, but haven't used it, yet. I was mainly wondering how much junk is going to get thrown through my rifles since I think .22lr is pretty dirty. MOA accuracy isn't as important since I'm talking 10 to 15 yard paper target silhouette drills, loading, reloading, transition to sidearm, etc. I want more trigger pulls and cheaper than $0.25 each. I guess I'll run it this weekend and see how I like it. I guess I can always build a dedicate upper later.
     

    kingfhb

    NRA & USCCA INST. w/ LSP#
    Rating - 100%
    26   0   0
    Mar 28, 2014
    3,060
    38
    New Orleans, LA
    I have the CMMG BCG Conversion kit and 3 mags... the only issue I had was with one magazine that needed a tab to be shaved down (actually part of the instructions included with the magazine). The BCG Functions perfectly... the end of it is a .223 casing so it fits in the chamber. It doesn't use your buffer or spring, but rather a set of springs on the BCG that do the job.

    Does leave some residue on your barrel and dirty up your AR... but if you don't mind cleaning it and have some "bore cleaner" laying around... its a great conversion kit. I have spitballed getting a dedicated upper for years... couldn't justify it when I already had the conversion kit. With the conversion kit TEEEEECHNICALLY you could even lose the Buffer tube, Buffer and Spring if you really want to spice up the build or wanted to build up a REALLY small .22LR pistol.

    I would even say if you have an old upper laying around you could just leave the CMMG bolt with it and bingo... dedicated upper... But the instructions specifically state "DO NOT LEAVE THE CONVERSION BCG IN THE FIREARM WHEN NOT IN USE" -- I am assuming because of corrosion possibilities from the ammo and contrasting metals.

    Bottom line... great conversion kit... shoots great... fun to shoot... fun for the whole family! :)
     

    thperez1972

    ESSAYONS
    Staff member
    Gold Member
    Rating - 100%
    10   0   0
    Dec 28, 2015
    5,713
    113
    Baton Rouge, LA
    With the conversion kit TEEEEECHNICALLY you could even lose the Buffer tube, Buffer and Spring if you really want to spice up the build or wanted to build up a REALLY small .22LR pistol.

    pffft...why would anyone want to do that?

    InkedIMG_0478_m_LI.jpg
     

    Tboy

    Moving forward
    Rating - 100%
    87   0   0
    Jul 14, 2008
    1,636
    48
    Greenwell Springs
    I’ve got one and several mags. All works as designed and it’s plenty accurate for doing drills and plinking out to 50 yds. I’ve been using plated .22 and so far I’ve not had any issues when going back to .223.

    FYI Cddn runs the mags on sale for $9.99 sometimes.
     

    tallwalker

    Well-Known Member
    Rating - 100%
    19   0   0
    Jul 24, 2012
    1,002
    38
    Covington, LA
    I have had the CMMG conversion kit for about six years. Had the original revision. Got it more as a convenience and a way to get cheap trigger time using my regular lower. Never have had a hiccup but I did also wear it out after many (many) rounds. Called CMMG and they sent me a whole new one free of charge last year. I was so pleased I ordered a ded 22lr upper from them at the same time. FAR more accurate and proper length, bore size, and twist. It wears a NV scope and suppressor. It is a hoot of a pest machine.

    As far as lead and crud, I can’t help but think that is an exaggeration. I clean my guns. No big deal with any caliber. If you are too lax about that seems like more of a shooter problem to me.

    For comparison, I also have an expensive Compass Lake A2 for high power practice. Whole different league in terms of price, but honestly don’t see much difference in accuracy. Wind calls are WAY more of a factor with that little bullet no matter what you do.


    Sent from my iPad using Tapatalk
     

    BSGA

    BSGA
    Rating - 100%
    4   0   0
    Mar 2, 2008
    197
    18
    Southwest,Louisiana
    I've had one for a while, at least 6-7 years. Great little conversion. Fairly accurate out to about 50 yrds. The stuff about crud is much ado about nothing. I've found I get tired of loading mags way before the barrel and upper gets enough crud to be a problem. Just go have fun with it. Great for the kids to get accustomed to the AR platform and teach good shooting habits. Always wanted a dedicated upper too, just couldn't justify the extra $'s. This fills the gap nicely for not much money. I did have to do a little polishing on the feed ramp initially to get it running right, plus, mine likes to run wet. It definitely has ammo preferences so get a variety of .22 to try out in it.
     

    Doctor481

    Well-Known Member
    Rating - 100%
    1   0   0
    Jan 28, 2013
    406
    18
    Ponchatoula
    I had 2, gave son in law one of them. Works OK, great for low cost drills. I started looking for better accuracy, so built up a complete AR with a dedicated 22 upper, also CMMG.
     

    bush_hog

    Well-Known Member
    Rating - 100%
    49   0   0
    Jul 8, 2007
    863
    18
    Covington
    I had 2, gave son in law one of them. Works OK, great for low cost drills. I started looking for better accuracy, so built up a complete AR with a dedicated 22 upper, also CMMG.

    This is exactly why I was looking at using this setup. Thanks for the feedback
     

    rcm192

    Sic semper tyrannis
    Staff member
    Rating - 100%
    111   0   0
    May 31, 2010
    6,207
    63
    New Orleans area
    I have a dedicated upper that I built with cmmg parts. Its excellent and a boat load of fun with the binary trigger and a can.

    I polished all friction points with flits very heavily. Probably wasnt required but it was fun to do and helped it run faster. Id like to see a np3 plus coated cmmg kit...it would be self lubricating and very easy clean up.




    I really need to get a drum mag now. I wish gsg would make the 110rd drums for the conversion guns.
     
    Last edited:

    340six

    -Global Mod-
    Staff member
    Premium Member
    Rating - 100%
    5   0   0
    Apr 12, 2012
    6,499
    113
    Kenner, La
    What is a good quality but not overly costly upper? Or is there not such a thing.
     

    Crazylegs8508

    Well-Known Member
    Rating - 0%
    0   0   0
    Aug 18, 2019
    59
    6
    Cincinnati ohio
    Ofc any 22 is going to be dirtier and the cmmg is great for a conversion but as always with any conversion it is not flawless and will not be as good as a 22 dedicated upper. With how cheap AR parts are now I would just do the upper bc if the liberals have their way prices are going to go up.
     

    Staff online

    Forum statistics

    Threads
    195,225
    Messages
    1,546,107
    Members
    29,169
    Latest member
    LanceK
    Top Bottom