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3/25/2012 7:58:40 AM EDT
I took my M&P15/22 out for the first time yesterday anr it shot great. Problem was that the rear takedown pin kept walking out. From looking at the pin it look like a lock washer should be holding it in place.
Anyoe else have this problem?
3/25/2012 1:50:27 PM EDT
[#1]
By any chance did you replace the stock pistol grip with an after-market
accessory? I ask this because the rear take down pin detent (plunger) and spring
co-reside with the safety selector plunger and spring under the grip. Quite a
few owners expected it was retained by the receiver extension plate (yeah, the M&P15-22
doesn't have those) and concentrated on only the selector detent (plunger) and spring, losing the others
when they changed grips.

In any event, if you aren't going to send it back to S&W, you can carefully remove the grip and
check to see if both plungers and springs are present and in working order. Your lower is polymer
and sometimes there is a burr in the hole that keeps the detent from seating. It is an easy fix, all
you need is a twist drill the appropriate size for the detent hole, and holding the drill with your fingers,
twist it until the burr (or shavings) are gone.

But I suggest you call S&W and have them go over the entire gun. They do great work.

Ted
3/26/2012 12:21:24 PM EDT
[#2]
Quoted:
I took my M&P15/22 out for the first time yesterday anr it shot great. Problem was that the rear takedown pin kept walking out. From looking at the pin it look like a lock washer should be holding it in place.
Anyoe else have this problem?


This: http://www.youtube.com/watch?v=S4LJP8d-LKw
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