New Colt 6951 doesn't go bang!

[Candyman87]

Finally got the new Colt 6951 9mm AR-15 to the range the other day. Long story short, I loaded it up, pulled the trigger, and CLICK. Nada.

Ejected the round, and had a light primer strike. Figured cheap ammo, and chambered a new round. CLICK. Nada.

Ejected and same story.

Knowing what I know about Colt's record with this gun, I assumed the barrel nut was loose. Got my armorer's wrench and it was cranked down to at least 35 ft. lbs. It didn't budge.

I've cleaned out the BCG and firing pin channel. Looks like I'm getting about .06" of firing pin protrusion. What should I be expecting from this gun?

Any other places to troubleshoot? I'd rather not deal with shipping back to Connecticut for repairs since I'm in the middle of a move then out of the country for a bit. I'd just hate to wait until May to get it fixed.

Thoughts? Resources for troubleshooting a 9mm AR?

[Smokin338]

Is the Colt a complete factory build or just upper and what brand of ammo ??

[Candyman87]

Complete factory build. 2013 configuration. Was shooting Remington UMC. Will try other brands of ammo on my next range trip as well.

[T2C]

The first place I would look is at the hammer spring. Does it appear to be installed in the lower properly? Maybe someone on the assembly line was having a bad day.


0.060" should be plenty of firing pin protrusion to ignite a pistol primer. Are the light primer strikes centered on the primer?

[Candyman87]

The first place I would look is at the hammer spring. Does it appear to be installed in the lower properly? Maybe someone on the assembly line was having a bad day.

0.060" should be plenty of firing pin protrusion to ignite a pistol primer. Are the light primer strikes centered on the primer?
Hammer spring appears to be installed properly. Primer strikes are indeed in the center of primer.

[Singlestack Wonder]

Check the chamber. Make sure there is no lube or anything else that would prevent the round from fully seating. What happens is that if the round is almost fully seated and the firing pin hits the primer, it pushes the round the rest of the way into the chamber before fully compressing the primer enough to go off.

[Waylander]

Do you own a 9mm pistol? If so, try firing some of the same ammo in it.

[Candyman87]

Do you own a 9mm pistol? If so, try firing some of the same ammo in it.

Of course! Ran five boxes through my G43 without a single hiccup.


Check the chamber. Make sure there is no lube or anything else that would prevent the round from fully seating. What happens is that if the round is almost fully seated and the firing pin hits the primer, it pushes the round the rest of the way into the chamber before fully compressing the primer enough to go off.

Ding ding ding! I think we have our winner!

Cleaned up the chamber on your advice and took the pony out to the range. Ran 150 rounds through it using some Blazer Brass 124 grain and the Remington UMC 115 grain.

Now that it's up and running, it's running smooth. No hiccups at all but damn, that's a dirty shooting gun!

Thanks for the help. I'm a big fan of this gun!

[usmcvet]

This place rocks! Great to hear your gun is up and running. It's also good info to have in my brain housing unit!

[Candyman87]

Sure does! If it weren't for this place I would have already sent it back! Thanks to all!

[usmcvet]

How many rounds do you think you Fired to get it that dirty?

[Candyman87]

I had about 150 rounds through it without any hiccups.

I've yet to have the opportunity to shoot it more. If I could get someone to pay for the ammo, I'd happily torture test it for you all!

[lsufan1971]

just a heads up. I would invest in a Spikes ST-9x 9MM buffer. It will make your gun much more reliable.

[Candyman87]

Thanks. I'll keep that in mind should I start having reliability issues.

[khc3]

Do new Colt 9mm's come with a buffer spacer?

[Candyman87]

Do new Colt 9mm's come with a buffer spacer?

Yes it does. Nothing fancy.

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