A couple of follow-up items. On the last day of the TAPS class, I dropped out of the walk-back drill earlier than I expected, missing a relatively easy plate shot at 35 yds. I figured I was just tired and flubbed the effort. When I recently went shooting, I discovered that one of the two RMR retaining screws was missing from the M&P45 training pistol I used at the TAPS class, allowing the RDS to wobble just a bit…and yes, the screws were initially installed with blue Loc-Tite. The slide milling by Mark Housel was done nicely enough to provide a reasonably tight fit for the RMR, so even with one screw missing I was still able to make close range hits; it was only at longer distances that the subtle looseness of the sight became critical enough to induce misses. Lesson learned—periodically check the RDS screws, especially after each day shooting in a higher round count class.
With the M&P45-RMR down awaiting the arrival of a new screw, I instead shot a G19-RMR for this recent training session. I ran the same pattern of drills used during the TAPS class, including shooting the 500 point aggregate at 25 yards. I was also curious to see if there was any advantage to using a G17 equipped with an RMR, compared to a G19. Obviously, with iron sights a longer sight radius can be an advantage when shooting at smaller, more distant targets, however this should not matter with RMR equipped pistols. With the G19-RMR I shot a 461 on the 500 point aggregate, the G17-RMR resulted in a 465--basically the same. If the shooter does their job, a G19, G17, and M&P45 all offer acceptable accuracy for duty/CCW use.
In another turn of events, I let my son shoot the M&P9 that seemed to be problematic during the TAPS course. Over the course of 300 rounds of Federal 147 gr FMJ and Winchester M882 ball, no malfunctions of any kind occurred…