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Hitmanflyer
09-03-10, 21:41
I shot my ar for the first time today, and I'm having an issue. I built it myself with a DPMS lower and a Del-ton upper assembly with a standard trigger. It will shoot the first shot fine then ejects the spent shell and loads the new shell just like it should. Then I go to pull the trigger and nothing happens: no clicks, bangs, or anything. I ejected that round and it looks like the firing pin hit the primer lightly but it didn't go off. I tried multiple times with the same effect.
Hmac
09-03-10, 21:53
No click when you pull the trigger, so the hammer isn't falling? Are you sure you installed the hammer spring right? Disconnector installed right? The light strike on the primer could just be firing pin momentum as the bolt closes - not uncommon.

You did a function check? Charge -> pull trigger -> hammer falls -> keep trigger pulled -> charge -> release trigger -> click (disconnector) -> hammer stays cocked -> pull trigger -> hammer falls

http://mccollister.info/hammerspring.jpg
Iraqgunz
09-03-10, 22:00
Please try and provide a little more info. What type of ammo were you using? What position was the hammer in? Was it forward?


I shot my ar for the first time today, and I'm having an issue. I built it myself with a DPMS lower and a Del-ton upper assembly with a standard trigger. It will shoot the first shot fine then ejects the spent shell and loads the new shell just like it should. Then I go to pull the trigger and nothing happens: no clicks, bangs, or anything. I ejected that round and it looks like the firing pin hit the primer lightly but it didn't go off. I tried multiple times with the same effect.
Hitmanflyer
09-03-10, 22:58
I was using Remington UMC 223 55 GR. MC ammo. It would work the first shot but the second shot out of the mag it wouldn't fire. I didn't look at the hammer after I miss fired. I looked at the spring and it looks like its in the right position. Thanks for the help so far.
Iraqgunz
09-04-10, 00:32
Ok, well let me say this first. You can either accept it or not. DPMS and Del-ton are not quality. UMC ammo is known to be somewhat underpowered as well. So it may just be a combination of all of the above.

You need to try and determine what position the hammer is in when it does this. Is it forward with a round in the chamber or is it to the rear? My guess is that it's forward.

Strangely enough another member had a similar situation with a Del-ton upper and he posted about it in the NFA area. A few other things.

1. Check the bolt carrier key and ensure that it is tight and staked properly.

2. Check to make sure that the gas tube is pinned and there is no excess leakage around the FSB area.

3. Go down and buy some Federal M193, M855 or Hornady TAP ammo and try it out. DO NOT USE RELOADED CRAP.

I suspect that possibly you are having an issue where it is overgassed. But, that is internet diagnosis.


I was using Remington UMC 223 55 GR. MC ammo. It would work the first shot but the second shot out of the mag it wouldn't fire. I didn't look at the hammer after I miss fired. I looked at the spring and it looks like its in the right position. Thanks for the help so far.
jwperry
09-04-10, 01:04
I was using Remington UMC 223 55 GR. MC ammo. It would work the first shot but the second shot out of the mag it wouldn't fire. I didn't look at the hammer after I miss fired. I looked at the spring and it looks like its in the right position. Thanks for the help so far.

When you pull the trigger, do you hear it 'pop'? It sounds like your hammer isn't being reset. Could be the weak ammo short stroking or it could be your disconnector isn't working right.
Hitmanflyer
09-04-10, 12:33
When you pull the trigger, do you hear it 'pop'? It sounds like your hammer isn't being reset. Could be the weak ammo short stroking or it could be your disconnector isn't working right.

Thanks for all the help. Right now it looks like my disconnector is the problem. When I function check it, after I charge it I don't hear a bang or a click. When I click the safety to safe it resets. Once I put it back into fire mode the hammer will fall. How would I go about fixing this problem?
Iraqgunz
09-06-10, 18:12
You need to ensure that the spring is installed correctly. Or if you have any doubts replace the spring all together.


Thanks for all the help. Right now it looks like my disconnector is the problem. When I function check it, after I charge it I don't hear a bang or a click. When I click the safety to safe it resets. Once I put it back into fire mode the hammer will fall. How would I go about fixing this problem?
Hmac
09-06-10, 18:50
In assembling your lower, did you confuse the disconnector spring with the bolt catch spring? The disconnector spring is tapered...
Blowby
09-07-10, 11:22
Thanks for all the help. Right now it looks like my disconnector is the problem. When I function check it, after I charge it I don't hear a bang or a click. When I click the safety to safe it resets. Once I put it back into fire mode the hammer will fall. How would I go about fixing this problem?

Disconnector spring not in place or weak or incorrect spring. The safety lever will lift the rear of the trigger assembly (disconnector as well) up and rock towards the hammer and engage.