Issue with my AR build

[Soccerdad1995]

OK, so I have recently completed my first (mil-spec) AR lower build, put a fully assembled upper on it, and finally got a chance to take it to the range. Only one issue (so far).

I lock the bolt back, insert a full 20 round magazine, release the bolt take aim, pull the trigger, and nothing happens. The trigger appears to not be resetting. No click, no nothing. When I then follow my SPORTS training, a round ejects with the pull of the charging handle, so a round did feed initially, and everything works fine from that point on. I can fire the entire magazine. Next mag, same issue.

So what did I do wrong with this build? I'm thinking it's something with the trigger???

[bubba84]

Are you "riding" the charging handle when you load the first round? Possibly not allowing the bcg to fully close.

Take the upper off and look at the "legs" of the hammer spring. They should be on top of the trigger pin.

Unassemble and reassemble the lower, maybe you missed something.

[RicoTX]

I agree with Bubba, make sure you pull the charging handle back and let her rip when loading a new magazine. I was doing the same thing when I first got my sport ii. If you still have the issue, then I would take it apart and double check everything.

[Wag2323]

Does everything work with a function check on an empty rifle? Pull the trigger and hammer falls?

Have you tested the trigger assembly without the upper on the rifle? You can use your hand to stop the hammer from hitting the frame.

[boxermoose]

Does everything work with a function check on an empty rifle? Pull the trigger and hammer falls?

Have you tested the trigger assembly without the upper on the rifle? You can use your hand to stop the hammer from hitting the frame.

Yup, gotta make sure the hammer spring is the right way around. So with the upper off pull the hammer back, make sure it locks, put your thumb in front if it so it doesn't hit the lower & make sure the trigger releases it

[C-dub]

Doesn't all that depend on whether or not the OP is loading that first round by releasing the charging handle or or the bold catch lever? Most of the time I thumb the bolt catch lever to load that first round after inserting a fresh mag and have had no issues.

[Soccerdad1995]

I'm loading the first round by hitting the bolt release lever. They taught me well in Basic Training not to ride the charging handle, so that's not the issue. I'm guessing it is probably the hammer spring. Everything function checks fine when the rifle is empty, assembled and with just the lower, although I have not checked the specific sequence of locking the bolt back on an unloaded mag, releasing the bolt catch and then dry firing.

I will check the hammer spring and failing that just do a complete disassemble and reassemble.