AR Trigger doesn't reset

[warpig]

Went to the range with my friend the other day, and we shot his newly purchased AR. After about 50 rounds, the trigger was starting to click on its way back from pulled, as it was moving forward. Within the next mag, would not return to the fire position - it was almost staying where it was pulled. You couldn't push the trigger forward back into position either.

Flipping the safety from fire to safe back to fire didn't do anything. I plan on taking apart the lower with him, and looking at the trigger spring, and make sure everything is in place there. Any other ideas?

 

[Tackdriver VillenTactical]

I have seen this a few times. Every time it was excessive material on connection between the disconnect and the hammer. I ended up having to lightly file the part of the hammer that catches the disconnect a few thousanths of an inch.

Dave

 

[dgrafton]

Is it a stock, basic lpk single stage? Did your friend do any 'improvements' that he saw online? Did he function test before finishing assembly?

There's not a lot to it. I just walked a friend through assembly last night, and explained how the reset worked and everything.

Sounds like he either tried 'fixing' or missed something on assembly. Check to make sure disconnector spring is in position.


Sent from my iPhone using Tapatalk

 

[mac1911]

Could be a popped primer in there too...
Did your friend clean and lube his gun before shooting?

 

[dgrafton]

Just saw that you said purchased. Just woke up and thought assembled.


Sent from my iPhone using Tapatalk

 

[scatter]

My first guess is disco spring upside down; second guess would be burrs on the disco itself. It would not be out of the question for a factory assembled gun to have these problems. What's the brand?

 

[Mattyd7]

I bet when you look into the lower you will figure it out pretty quickly. Either something like a primer stuck in there or a broken spring. I'd be surprised if you needed to file off material since it was working earlier. But who knows.

Also, make sure that the hammer springs are riding on top of the trigger pin. One time I put it together with the hammer spring resting against the bottom of the lower and it had a similar effect.

 

[miken2006]

Based on my experience the disconnector needs a good lube and break in period... Since its a new purchase and not a build i assume the disconnector spring is on correctly... To speed up the break in u can remove the disconnector and take a few passes of 2000 grit sand paper to the shiny side. Good luck

 

[warpig]

Thanks all. I'm not sure what kind of LPK/lower he has on the AR, but its not factory assembled - prior owner built it. I also don't know if there was any cleaning/lubing of the lower prior to us going out though. I'll follow up with him

Most likely, we'll pull it apart. I've got most of a spare LPK laying around, so we can replace anything that looks worn out. Thanks for giving us a few areas to look at as we go.

 

[ColdDayInHell]

I bet when you look into the lower you will figure it out pretty quickly. Either something like a primer stuck in there or a broken spring. I'd be surprised if you needed to file off material since it was working earlier. But who knows.

Also, make sure that the hammer springs are riding on top of the trigger pin. One time I put it together with the hammer spring resting against the bottom of the lower and it had a similar effect.

Yep. Should be painfully obvious. Check the hammer springs.

 

[Dadstoys]

Sounds like either a spring issue or a primer jammed up.
I would caution against filing any fcg parts unless you really know what you doing.
Most of the case hardning is very thin and if you go to deep your down to a much softer metal that will wear out much quicker than normal.
Full auto is only fun when you know it's coming

 

[dgrafton]

OP, post what you find out. Will give others a heads up down the road.


Sent from my iPhone using Tapatalk