Help, AR goes 'click' No fire.

[lear60man]

I have approx 300 rounds on this build and I can imagine the firing pin taking a dump this quickly. But then again this is my first AR. Yes I was using cheap ammo but it did the same thing with the good stuff. So anything I might want to check or replace?

Here are pics:

[BroncoBob]

Hard primer or weak hammer spring.

[desertdweller]

but it did the same thing with the good stuff. So anything I might want to check or replace?

or weak hammer spring.

+1 on the spring.

You can also check and clean the bolt where the pin goes, in case there is debris. Also the bolt head to make sure the round seats fully.

[G-forceJunkie]

Most AR's will put that dimple on a primer just by loading it. The firing pin is floating, it smacks the primer every time a round is put into battery, but not enough to fire it. Are you hearing the hammer fall, and yet it does not fire? Or is the hammer following the carrier down? Is the bolt/carrier going all the way into battery? Is your hammer spring in backwards? Check the firing pin portrusion? Those are the things I would check first.

[nicoroshi]

Most AR's will put that dimple on a primer just by loading it. The firing pin is floating, it smacks the primer every time a round is put into battery, but not enough to fire it. Are you hearing the hammer fall, and yet it does not fire? Or is the hammer following the carrier down? Is the bolt/carrier going all the way into battery? Is your hammer spring in backwards? Check the firing pin portrusion? Those are the things I would check first.

This^^^^

[desertdweller]

If you want to check to see if your springs/parts are assembled correctly, this has a lot of great diagrams:

http://www.ar15.com/content/guides/assembly/lower/

[Norm222]

Post #3 has a good photo of the hammer spring.

http://www.calguns.net/calgunforum/showthread.php?p=5279107

[knucklehead0202]

buy an ak?

[E-120]

My guess is the spring is in backward.

[lear60man]

Ok, Firstly thanks for the responses. I really appreciate it.

Everything in the lower is put together properly...I just did a re-assembly to verify. Trigger Group/Hammer functions as advertised.

New Info: My Buffer Tube was not fully pushing down the buffer retention pin. It was one turn aft (back) and thus the Buffer/Buffer Spring shot forward when I dis-assembled it.

So I have two theory's:
1- The Buffer Tube wasn't properly forward as spec.
2- The Firing Pin has worn down. This is why I posted a pic. From what I have gathered a worn pin tends to mushroom. Mine still looks new (only 300 rounds).

Thanks again for the knowledge guys.

[G-forceJunkie]

If the buffer tube is one turn out and lets the pin pop up, and you have a carrier with a closed end, it will hold the carrier just shy of locking up in battery. Fix that and you probaly have fixed your problem.

[captbilly]

Does not look like a bad firing pin

Firing pin stuck , from dirt, (take bolt carrier group apart and clean)? Hammer spring not on top of trigger pin but underneath. Cracked hammer spring, this would be very early for such a problem but it could happen. Hammer is releasing as bolt goes forward rather than when you pull trigger (as per another post). Hammer has slid sideways and is hitting the bolt carrier on it's way to firing pin.

[Travis Bickle]

I'll go with cleaning

Likely some crud in preventing free travel

[lear60man]

Thanks again folks.

Parts were cheap so I went ahead and changed the firing pin and hammer spring. Through cleaning and properly repositioned the buffer tube. Ill hit the range next week and post an update.

[Jeff Taylor]

Same thing happen to me. I had removed my stock the night before for inspection. During reassembly, I didn't tighten the tube far enough in to cover the buffer pin and hold it in place. So consequently, the buffer spring would go haywire and the gun would go click with no fire. I discovered my mistake with the help of a friend and fixed it on the line. Bingo, everything works great now. Im sure that was your problem as well. Good shootin'. JT