Bolt Catch? Short Stroking????

Discussion in 'AR-15 Discussion' started by Steelersfan, Jun 24, 2010.

  1. Steelersfan

    Steelersfan New Member

    Put a perfectly functioning upper on a new Spikes lower with DPMS parts kit and an Ace Skeleton Buttstock. Everything worked great, unloaded a 20 round mag but when the last round was fired, the bolt did not lock to the rear by the bolt catch. The bolt was closed. I pulled the charging handle back and the bolt catch worked. I loaded the mag with one bullet and fired to test the bolt catch several times, and it never caught. I have read a little about short stroking but not really much. Is it possible that because the spring and the buttstock are new that it might not be allowing the bolt to travel far enough to catch open after the last round? Any other reason this would be happening?? I am relatively sure it is not the ammo, because it works fine with the same upper on a RRA lower. Any help would be great!!! Thanks.
  2. Quentin

    Quentin New Member

    Well anything's possible when you mix'n'match. First did you verify that the carrier gas key is screwed down tight and staked properly? Does the Spikes lower have the heavy Spikes buffer/spring? Maybe try the RRA buffer and spring in the Spikes to compare. Also have you tried more than one magazine? And what ammo did you use?