Mr Apperson wrote an excellent description of the trigger reset action. His use of the terms front (top) nose and side noses is very descriptive and accurate. Unfortunately the average home 'smith isn't likely to take apart the trigger mechanism to get at the trigger lifter. Take a look at the springs and parts inside and that will dissuade most everyone but the real experts. If the sear tail inspection shows they are exactly in line with each other when the hammers are cocked, and the screw loosening and tightening doesn't help, I personally would send the gun away for repairs. Incidentally the M21 single trigger design is excellent. I hope this thread isn't casting any negative impressions on the M21. I've used all but one of my "original" guns extensively with nary a problem. Yep, you might find a problem child now and then, but you will also with most any gun. Silvers
