S&W M&P 15-22 trigger pins took a walk

[Little Dutch]

I have a LaRue flat trigger in my S&W M&P 15-22. It's been in there for a about a year, and shot quite a bit. Not a ton, but 600 rounds or so. I took the rifle with me yesterday to do some outdoor shooting and noticed the trigger pins had walked out.

A set of anti-walk pins do not cost terribly much, so it's an easy fix. But this is the first time I've had a receiver to that. Do you think it has something to do with the polymer receiver? Anyone else have an aftermarket trigger do that with the 15/22?

[powerstroke79]

Had it happen with a factory trigger group. Bought a set of anti-wall pins, not a single problem since.

[Eric P]

I think there is not enough friction with the polymer or the hole is slightly larger than the pins. Mine walk slightly everytime I use it. I just placed black electrical tape over the holes. They move slightly, but the tape keeps them in place. A dab of hot glue should also work.

[CS1983]

I have two. I have never noticed it on mine. I'll take a peek and see if there is evidence of it.

[Little Dutch]

On that note, I've never had to put in anti walk pins. Do you prefer the dog-bone style or just the plain-jain double headed pins?

Just two random examples of what I'm asking about:
Dog Bone:
https://www.midwayusa.com/product/1021312910

Not Dog Bone:
https://www.wingtactical.com/firearm-parts/ar-15/lower-receiver-parts/lower-receiver-parts/armaspec-stainless-anti-walk-pins/

[CS1983]

Either should be fine. If you go with the non-dogbone don't forget loctite on the screws.

[powerstroke79]

Been very happy with the KNS

https://www.midwayusa.com/product/1003368197

[whitewalrus]

Been very happy with the KNS

https://www.midwayusa.com/product/1003368197

KNS are good to go. I have them on a few lowers. They make a few different types.

[Gman]

Get pins designed for the S&W M&P 15-22. They are longer than the standard aluminum lower AR-15 pins.

https://www.knsprecisioninc.com/product/smith-wesson-mp-15-22-non-rotate-trigger-hammer-build-a-kit/

Non Rotate Trigger and Hammer Pins designed specifically for the Smith and Wesson M&P15-22. These pins are TOO LONG for regular forged aluminum AR-15 lower receivers and will stick out the sides quite a bit.

THE TORQUE SPEC ON THE SCREW IS 11 inch/lbs. MAXIMUM. We recommend 8INCH/LBS of torque.

***THIS IS FOR THE POLYMER .22LR S&W M&P15-22 ONLY. FOR ALUMINUM M&P-15 LOWERS, PLEASE USE OUR STANDARD NON-ROTATE PIN SETS. ***
I use KNS pins in my AR-15s. I notice the type I have are no longer made by KNS.

[Little Dutch]

Get pins designed for the S&W M&P 15-22. They are longer than the standard aluminum lower AR-15 pins.

https://www.knsprecisioninc.com/product/smith-wesson-mp-15-22-non-rotate-trigger-hammer-build-a-kit/

I use KNS pins in my AR-15s. I notice the type I have are no longer made by KNS.
good to know, thanks!

[CS1983]

Took a look at both of mine. No evidence of walking.

[Little Dutch]

Get pins designed for the S&W M&P 15-22. They are longer than the standard aluminum lower AR-15 pins.

https://www.knsprecisioninc.com/product/smith-wesson-mp-15-22-non-rotate-trigger-hammer-build-a-kit/

I use KNS pins in my AR-15s. I notice the type I have are no longer made by KNS.

I ordered a set of black Gen2Mod2 for the MP 15-22. I don't know if any of their different models are better than any other, so I based my decision on price. Again, thanks for the heads up on the 15-22 specific pins.
https://www.knsprecisioninc.com/product/gen-2-mod-2-build-a-kit/

[Little Dutch]

My pins arrived today. Joe Bob shipped fast! I placed an order with Brownells the day before I ordered these that finally shipped today.

I was going to post a photo but it won't let me upload from my phone.

[Little Dutch]

81086

[Gman]

Those aren't going anywhere. [Coffee]
[Awesom]

[powerstroke79]

Nice

[Little Dutch]

No one mentioned it, but after I took the picture I realized the selector switch was on the right side of the receiver.

[ChickNorris]

No one mentioned it, but after I took the picture I realized the selector switch was on the right side of the receiver.

Ha! Second time in this thread I've made an assumption... at first I thought everyone knew the 15-22 receiver was a bit wider & that wider pins are required (along with a couple other parts) & the second was that you had an ambi selector & liked the long. Silly me.

[CoBoneDoc]

Little Dutch-like others have said thread locker is vital for these. I have had two polymer lowers and one alum have the pins walk. Because of this I now use the anti walk pins on all my builds. Simple, cheap and rectifies the issue although rare, no more concern.