Bolt wouldn't open,

Halfnutz

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  • Jan 14, 2008
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    Peoria County, Illinois
    Went out coyote hunting this morning with LMT CQB MRP 16in CM barrel. No dogs, but dropped a crow, missed 2 more. My fault, no excuses. Ammo is 55gr vmax, in multiple fired brass.
    Any way once I got back to the truck and attempted to clear the rifle, the bolt would not retract. I fired the rifle into the ground after removing the mag to clear it. I'm suspecting it has something to do with the ammo as it was loaded for a different rifle. I have had this issue once before with some other ammo that was loaded with the same dies. Never had any issues with factory ammo. Didn't think to police the brass, to double check it. Any one else have an issue like this with an AR. Realizing this is prolly just an ammo issue. Anything else I need to check?
    Thanks.
     

    kraigWY

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    Feb 10, 2006
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    Re: Bolt wouldn't open,

    Chances are the shoulder wasn't set back far enough when you resized the brass. Common among gas guns, that's why they make case gages to set up the sizing dies.
     

    shootist~

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    Apr 1, 2010
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    Re: Bolt wouldn't open,

    Get a chamber check gauge to set your sizer die adjustment (and loaded ammo). Probably go with some newer brass as well. Ditto on checking the trim length mentioned above.
     

    jrnm

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    Dec 25, 2011
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    Re: Bolt wouldn't open,

    Have had the most problems with excess length brass, but I just recently had a gas ring that came out of the groove and bent back, had to drive the bolt back with a brass rod, then it was stuck in the rear position.
     

    MikeEzell

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    Feb 1, 2009
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    Re: Bolt wouldn't open,

    IMO new brass is the cure but a small base die may well get you a few more firings from the brass. IME brass that's been fired several times in a chamber that's obviously bigger(any bigger at all) than the new one will eventually get tight again, even after sizing it with a smaller die or bumping more. YMMV.--Mike