Please excuse if this is covered elsewhere, and just steer me to the appropriate thread.

New M&P began short stroking after the first ~150 rounds, which I eventually found to be because the bolt-carrier key had loosened. The key screws had stake marks from the factory, but which obviously didn't hold. A firm twist on each screw was able to seat them about a 16th of a turn deeper than where they had originally been staked. Another 120 rounds were then shot w/o further problem.

The key screws are still holding as re-tightened, but should I re-stake them as well? If so, how?

I'd like this to be a fix-it-n-fergit-it scenario - thanks.