My Victory had a loose screw twice in the first 100 rounds. I cleaned the screw and hole well put a drop of purple Loc Tite on the screw and screwed it in then back out to get the stuff on all threads then torqued to 40 inch pounds with my Fat Wrench. 1360 rounds now and it hasn't moved. I put a small mark on the screw head and one on the frame with white paint pen so I could see if it moved, it hasn't. Had the same problem with the screws holding the rail and used blue on them but only 14lbs torque. You also need to wait 24 hours for the Loc Tite to completely cure. Other posters have used other methods on this forum that has worked for them. I really don't know what S&W could do to fix this but I like the gun so much I could live with it even if it kept coming loose. With the Volquartsen barrel this gun will out shoot my new Mark III Competition using the same optics and bench rest on both guns.

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USN Retired/VN VET
M&P X5