CMMG .22 Conversion Problem

Discussion in 'GSSF' started by LoadToadBoss, Nov 5, 2010.

  1. LoadToadBoss

    LoadToadBoss IYAAYWOT

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    I bought a stainless steel CMMG .22 conversion for my M&P-15OR about a month ago. I've used it on three range outings firing about 125 rounds each time with no problems. Using my Primary Arms 1-4x30 scope, I've been able to shoot a 25rd mag into an area the size of a half dollar at 35 yds.

    Today I was shooting nice tight groups through 150 rds. Then all of a sudden the rounds were flying wild. I thought at first my scope loosened up and was rotated. Nope; that was fine. Then I thought I might have canted the rifle, so I paid attention to that; no help.

    I noticed that the rounds were all over the place. There was no consistency. I noticed also the the holes in the target were the size of .45 cal instead of pin point holes indicating that the rounds may be tumbling.

    Has anyone else had similar problems? If so, was it due to residue build up? I'm open to suggestions. I've cleaned the rifle and bolt. Hopefully that will help.
     
  2. raven11

    raven11

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    try emailing CMMG

    I had my .22 conversion for about the same length of time and i'm up to 2,000+ with no problems
     

  3. FelixD

    FelixD

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    I suggest the bore and chamber be cleaned as a starting point. If the ammunition remained the same, and was not changed during the session, the sudden decrease in accuracy would most likely be traced to the bore. Also, remember if you are shooting .22 LR in a .556 bore the .22 LR bullet is undersized. An undersized bullet will limit accuracy to start with.
     
  4. LoadToadBoss

    LoadToadBoss IYAAYWOT

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    After a good cleaning of the conversion unit and the upper receiver, I took the rifle out for another range visit today. The rifle was shooting true and straight. I only shot 50 rounds. My best guess is that after 150 rounds or so, the unit will not be accurate, just like an overheated barrel will throw rounds off. Just something to keep in mind.