M&P 15 Sport lpk/trigger issue

[Michlale]

First time post and new owner of an M&P15 sport so take it easy on me.

So I’ll just begin with the back story.

About 2 days ago I bought a new M&P15 sport from a local shop. Was very excited to test out my new rifle so I took it to the range right away. When I was there I set up loaded my magazines with some Winchester FMJ 55 Grain rounds. Was using pre-ban 30rd mags just in case that may have something to do with the problem...doubt it though. Anyways, after loading and setting up my targets, I began to shoot. After about 5-10 rounds it stopped firing, thought it was a bad round so I ejected that one and same thing. I began to notice that it wasn’t the ammunition I was using that was the problem but the trigger. It would act as if the safety was on when in fact the selector was on fire. After a while it worked out by me switching it from safe to fire three to four times the hammer would reset and it would fire a few more rounds ...... then the same issue would occur. I decided to open it up again and making sure I didn’t let the hammer fly forward I started to dry fire it. To me it seemed as if the hammer was "over cocked" and to fix it I would have to stick my pinky in and gently push on the disconnecter and it would reset and would fire for 2-15 more rounds before the issue occurred again. I was very frustrated at that point having heard such good things about the rifle and this was happening.

I have experience with these types of rifles being military, but not this particular rifle itself.

Please if anyone knows what could be happening or what the issue is that would be great if you could help me out.

I will be bringing it back to the shop my next day off as I don’t want to mess with it any further, but I would like to know your guys thoughts on the matter.

Thanks in advance!!!!

[Natsmith77]

Did you or someone you know mess with the trigger at all? I have heard cases where someone fiddling with the triggers have put the springs back in backwards and causes the trigger to do crazy things.

[storeyteller]

Sounds like you're describing a problem with the disconnect? I know it sucks, but send it back to the mothership. They usually get it back to you pretty quick.

[oneyeopn]

You dont have to worry we welcome all comers. Welcome to the forum. By any chance did you clean it before you took it to the range, There have been occasions where dirt or gummy oil from manufacturing have been missed when shipped. A tiny shaving may have fallen into there and be causing the issue. Also what kind of gun lube are you using, the sports seem to like to be lubed well while being broken in. Other people may have other suggestions. I have heard of this before and it turned out to be a particle of dirt or something in there but I cannot really remember.

[JaPes]

I once had a hammer J-Pin break on me. A part of it lodged under the trigger, interfering with the disconnect.

Go on YouTube & look for AR trigger disassemble & reassemble videos. Pull your trigger out, check for anything odd or any obstructions. Wipe out the lower. Lightly lube the trigger. Reinstall & make sure the springs are in the right orientation.

If all else fails, use the best feature of the 15-Sport: S&W's limited lifetime service policy. Give the mothership a call.

[Buffalohunter60]

If its any help to you...I have the stock trigger out of my sport....it worked fine and was not bad....but I put a CMC trigger in it and I do not need this other trigger. I also have the rear sight that came with it but because I need a scope on everything I shoot...I dont need that either. I will give them to you if you can use them or want them...just give me a shipping address and they are yours. Best John