New AR failure to fire **Solved operator error**

Tiwaz

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OK new AR, I put the first 50 rounds through without an issue now I am getting light primer strikes about 10% of the time. Different Mags 6 Pmags , different ammo (Winchester White box 55gr FMJ & PMC X-Tac 62gr).
Before anybody asks the rifle was properly cleaned and lubed before shooting.

The bolt has fully cycled, just getting light strikes. Where do I start trouble shooting?
 
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So you pull the trigger and it doesn't go bang?
Correct
What brand gun is it? Or is it made from parts?
Not a parts gun
Did you change anything between the first 50 rounds and the rounds that are having light strikes?
I first started having this with the Winchester and then switched to the PMC the problem still pops up randomly. 25 rounds no problem then 3 in one mag then no thing again.
Take the BCG apart and clean. There may be some crap in the firing pin channel.
I was following a break in procedure of 5 and clean for the first 30 Rounds then I went to 25 and clean. Each time I cleaned I pulled the BCG apart and cleaned/inspected it as well.
 
Take the BCG apart and clean. There may be some crap in the firing pin channel.


that,

also take the bolt carrier group out and check that the fireing pin pokes out the little hole in the bolt face when you push the pin forward,

something may be in that channel, or your pin may have mushroomed, or had the tip chipped off.

I am assuming of course that the hammer is dropping properly

possibly check the springs and the hammer in the lower, also, using a dummy round, or a live one at the range, pull the action all the way back and let it slam into the (dummy) round, do you see a small indent on the primer?

if not either something is stopping the pin from travelling all the way forward, or there is too much space between the primer and the bolt fact for some reason.
 
Another item of note I have found some brass flakes on the face of the bolt intermittently as I was cleaning.I didn't think this was the cause though, if one round didn't fire all I was doing was clear it and chamber the next round(run the charging handle) and fire. There also seemed to be more of these flakes when shooting the Winchester.
 
Not a parts gun

I'm assuming that the gun is an NEA since you didn't want to mention brand. That and it seemed like you had one or two of them on order in another thread ;)

I don't think the firing pin is damaged or obstructed otherwise he would be having the problem more often than he is.

So my two thoughts are;

a) issue with the hammer spring. either the legs aren't sitting on top of the pin like they should be or the spring is weak

b) head space could be excessive enough that some rounds are seating deeper in the chamber than they should and the pin isn't reaching them

When it fails to go bang, is there any mark at all on the primer when you eject it? there should be even if you don't pull the trigger

One other thing; you're not lubing the firing pin or the hole it goes in, are you?
 
I'm assuming that the gun is an NEA since you didn't want to mention brand. That and it seemed like you had one or two of them on order in another thread ;)

I don't think the firing pin is damaged or obstructed otherwise he would be having the problem more often than he is.

So my two thoughts are;

a) issue with the hammer spring. either the legs aren't sitting on top of the pin like they should be or the spring is weak

b) head space could be excessive enough that some rounds are seating deeper in the chamber than they should and the pin isn't reaching them

When it fails to go bang, is there any mark at all on the primer when you eject it? there should be even if you don't pull the trigger

One other thing; you're not lubing the firing pin or the hole it goes in, are you?

a) Hammer spring legs are in the correct location
b) yes there are marks on the primer the firing pin has been lubed as per manufactures instructions (very light film of CLP) nothing into the firing pin channel though.
 
Is it a NEA? :rolleyes:... (I kid, I kid...)

I'd wager it is simply because it appears as if the OP is reluctant to say who the manufacturer is and start the inevitable chitshow that would follow. Can't say that I blame them, it's hard to get answers to questions when threads go sideways.

At any rate, to the OP, please let us know how you make out and what the issue turns out to be.
 
light hammer strikes are cause by hammer spring being either too soft or assembled wrong, check and makesure the 2 legs of the spring is sitting on top of the trigger pin.
 
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