So, got a brand new custom AR lower. Swap it out, take it to the range. It fires one round, cycles to the next, but doesn’t reset the trigger. Basically I have a live round in the chamber, but can’t shoot it. Tried two different mags and different ammo. Using same BCA and charging handle. It obviously fired before with the other lower, which I don’t have anymore b/c I’m a moron and got rid of it.
Any of you more intelligent AR folks know if this could possibly be an assembly error, or should I just send it back?
Was it a complete lower and you just attached to the upper with pins or did you build the lower? If all you did was take a complete lower and attach it to your upper, not much you can do to screw that up. Soulds like you have a issue with the trigger assembley, but personally wouldn’t know what the problem was without looking at it.
Need more info on upper and lower. What brands, is trigger assembly mil-spec, drop in, or some other type aftermarket, and what type of buffer. My guess is the buffer is not allowing the bolt to go quite all the way back to reset the trigger group. A rifle buffer in a carbine or a pistol length upper will cause this. There won’t be enough gas pressure to overcome the spring pressure.
Sounds like the trigger spring(s) is(are) installed backwards.
Tigerfin, he said it cycled and loaded the next round, so it cycled enough.
I’m betting on something in the trigger group. Either the disconnector spring or the trigger spring.
Does it cycle with the upper removed? Remove upper, place rifle on ‘fire’ and place your finger between hammer and lower receiver (never let hammer hit receiver, it can crack the aluminum). Let the hammer fall on your finger by pulling the trigger. DO NOT RELEASE THE TRIGGER. Now use your other hand like the BCG, ride the hammer rearward, and see if it catches on the disconnector. It should. Then release the trigger and it should engage the sear and be ready to fire. Does it fire?
OP, could you post a picture of the trigger spring arrangement?
Sounds like the trigger spring(s) is(are) installed backwards.
Tigerfin, he said it cycled and loaded the next round, so it cycled enough.
I’m betting on something in the trigger group. Either the disconnector spring or the trigger spring.
Does it cycle with the upper removed? Remove upper, place rifle on ‘fire’ and place your finger between hammer and lower receiver (never let hammer hit receiver, it can crack the aluminum). Let the hammer fall on your finger by pulling the trigger. DO NOT RELEASE THE TRIGGER. Now use your other hand like the BCG, ride the hammer rearward, and see if it catches on the disconnector. It should. Then release the trigger and it should engage the sear and be ready to fire. Does it fire?
OP, could you post a picture of the trigger spring arrangement?
Very easy to swap a spring in backwards when you’re assembling a pile of lowers…
Make sure there is even a disconnector spring between the trigger bar (lower portion, not the hammer) and the disconnector. That spring is also easily confused with the buffer retainer spring, and can cause all kinds of issues if wrong one is used.
No, didn’t get a chance to get into it last night. Wife had people over. Apparently it’s frowned upon in our house to disassemble the rifle at the dinner table while we’re “entertaining.” Women…
The first red flag here is a known CF.com liberal that has an AR-15… I’m leaning on the theory that he is probably putting the magazine in backwards. Anyone else???
Either that, or he purchased the “Obama Signature Series”, which will still hold a 30 round magazine, but will prevent the second bullet from firing.
No, didn’t get a chance to get into it last night. Wife had people over. Apparently it’s frowned upon in our house to disassemble the rifle at the dinner table while we’re “entertaining.” Women…
I’m gonna PM you my number. Text me a pic of the trigger group looking DOWN and I’ll get you straight.
Very easy to swap a spring in backwards when you’re assembling a pile of lowers…
Make sure there is even a disconnector spring between the trigger bar (lower portion, not the hammer) and the disconnector. That spring is also easily confused with the buffer retainer spring, and can cause all kinds of issues if wrong one is used.
GOOD LUCK! At least it’s something simple…
Wadmalaw native
16’ Bentz-Craft Flats Boat
you called it. When I cycle the lower manually as instructed, it resets and catches the disconnector, but doesn’t engage the seer unless I press the hammer down manually and let it pop up. Basically gets hung on disconnector. Sending it back to builder today, but man that was spot on.
I know next to nothing about AR platforms, not my thing. I know M14s pretty good though.