AR Fail to Fire Situation and my trouble shooting steps

JBoyette

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So I have ran an AR platform professionally and not, for over 22 years now. "damn I am old" anyhow, first time this situation happened to me or seen it.

I had a fail to fire two times in a row, first two rounds on the home defense AR. Rifle is on barrel #2 and was #3 ever built out of War Sport Industries before the brand had the GPR and LVOA.

So the why is The firing pin was so sluggish with oil and powder "mud" that it caused a deceleration of the firing pin after a hammer strike.

That's the why, now lets talk about the trouble shooting steps, I think this will be helpful for alot of you all.

Starting gun status: Magazine in, round chambered pointed at a paper target 50yds, selector on SAFE.
  1. Assume Sight Picture, rotate to FIRE. PRESSSSSSSSS, CLICK.
  2. Attempt to Place on SAFE, cycle action, observe ammunition with bullet still attached eject
  3. Cycle step 1 again
  4. STOP
  5. Unload magazine.
  6. Rotate ejection port towards the deck, cycle action, observe ammunition with bullet still attached eject
  7. Let bolt go home, rotate selector to SAFE
  8. Separate upper from lower, extract BCG.
  9. Observe barrel from Chamber side to see the light?
  10. I do see the light "no barrel blockage"
  11. Test hammer spring stiffness :"Passed"
  12. Go to BCG
  13. Test proper assembly, Lock the bolt to the rear, place finger on the back of the firing pin, does it protrude through the bolt face? "YES"
So at this point, the only other option is bad ammo. But I know its not. Been shooting this lot for a bit now. I go ahead and dissemble the bolt carrier group and wipe down the firing pin, cam pin and then insert the firing pin in the bolt, remove and wipe clean.

Every time I do the the firing pin goes in faster, comes out quicker and by the fourth time its super clean and easy, feels like it should.

Reassemble and the gun went back to running just fine all day long.

So I hope you can learn something fro this.

John
 
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John, just curious. How long/how many rounds fired since the weapon was cleaned?
 
John, just curious. How long/how many rounds fired since the weapon was cleaned?

Time since a wipe down? A year
Last time oiled up? 4 months ago
Last time shot? 2 Weeks ago
round count since last cleaning? 2000+???
Last time legit cleaned? 2018 i think???
 
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I'm not sure about your problem....but this part caught my eye...

  1. Assume Sight Picture, rotate to FIRE. PRESSSSSSSSS, CLICK.
  2. Place on SAFE, cycle action,

After you fire an AR and the hammer is resting against the frame I don't think it's supposed to allow the safety lever to rotate to safe. You can "safe" a charged weapon with a cocked hammer only I believe. How's that trigger and safety working?

What are the chances that the hammer got jammed on a blown out primer and didn't go through it's travel, thus allowing you to safe the weapon? Did you have a primer dimple on the round ejected?
 
I'm not sure about your problem....but this part caught my eye...

  1. Assume Sight Picture, rotate to FIRE. PRESSSSSSSSS, CLICK.
  2. Place on SAFE, cycle action,

After you fire an AR and the hammer is resting against the frame I don't think it's supposed to allow the safety lever to rotate to safe. You can "safe" a charged weapon with a cocked hammer only I believe. How's that trigger and safety working?

What are the chances that the hammer got jammed on a blown out primer and didn't go through it's travel, thus allowing you to safe the weapon? Did you have a primer dimple on the round ejected?

Great catch, I just edited to say "Attempt to Place on SAFE" I do that to trouble shoot.
 
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