During training one of the guys was attempting a double tap at close range.  On one trigger pull the rifle fired two rounds.  We only carry semi-auto rifles soooooo this should not have happened.  I know that when the bolt carrier loads a round that the firing pin will tap it somewhat (usually leaveing a small indent on the primer) but not enfough to cause a discharge.

The rifle itself was not fully clean and has ever done that before.  It's also about 5 years old.

I'm guessing that a new bolt carrier assembly will fix the problem.  Gonna contact Colt's LE divsion tommrow.

Comments, suggestions and/or past expericences???


Full auto is nice buuuut I don't think THE MAN would approve.

Thanks

David

It is not the bolt/carrier group that's the problem.
It is most probably your fire control group, and more specificaly
the disconnector.
Has it happened before or after this incident?
Has someone recently done work to the weapon?
Try the function check: (copied from trobleshooting forum)
Double check your assembly then dry cycle the lower by hand to check for mistiming. The tip of the disconnector should almost touch the middle hammer hook when you cock the hammer by hand. Keep something soft, like your thumb, between the hammer and lower in case the hammer slips. Do not allow the hammer to strike the lower. With the hammer cocked onto the disco, SLOWLY release the trigger. The hammer should jump up slightly and now be resting on the tip of the trigger. Repeat this several times. The hammer should not fall.

I have had this same problem on department guns. Gunslinger808 is right. It is most likely your disconnector or the disconnector spring. Have a trained armorer check it out. You do not want to expose yourself to that kind of liability if you are not trained. If you do not have a Colt LE trained Armorer in house call around to surrounding agencies and see if they have one. If not contact Colt and send it in to have them fix it.

Cool!!!!wish mine would do that!!!

Night Crew

As part of the training we function checked the rifles several times before starting.  Dry fire, keep the trigger pressed, charge the rifle, let up on the trigger and listen for the re-set and dry fire again.  No problems.  Thats why I did't think the problem was with the Lower.

I forgot about the spring, I'll have to break out my tools and remove the assembly and check it out.  thanks lucky stiff.

I'm the department's only armorer (2 day Arma Lite course, only course offered out here)  See what I can do.


Thanks!!

David

If you were closer I could take a look at it. Check the sear for wear, trigger area springs and pins as well.

Also you need to perform a firing pin test to check if the firing pin protrusion is excessive or your bolt may be out of speck.

Just a few hints since it’s hard to tell and not see the weapon or test fire it.

Quoted: Cool!!!!wish mine would do that!!!

No you don't.  With no auto sear, the gun is slam-firing and can go BOOM.  Also, BATF doesn't care if you are a cop or not- if you get caught with a gun that fires more than one round per trigger pull and you don't have a tax stamp, you are dinky-dau'ed.  They did that to a cop some years ago who called them to ask what he should do with his rifle that was doing the same thing.  They told him to send the whole gun back to the manufacturer for repair.  They intercepted the gun after the cop sent it, test fired it, and when they got it to double arrested the cop for unlawful possession of a machine gun.  The federal judge it went in front of dismissed the case and chewed BATF out, but he still went through hell for trying to do the right thing.

FOUND IT!!!

I removed the hammer and instantly found the problem.  A prior (and very appearent dumbass) someone removed the trigger spring and installed it upside down and all funkafied.  The trigger was being held up by the pin and the spring was just flopping around.  Now if it was me and I installed it that way I would be thinking ----Self, thats not right---springs arn't supposed to be loose.  There was some tension from the spring but only at certain time of the trigger pull.

So heres my quess....

At times the trigger tension was too lose and allowed the disconnector to release the  hammer which caused it to fire two rounds with one trigger pull.


After I CORRECTLY installed the spring both myself and the officer who is issued the rifle,  greatly noticed a heaver trigger pull.  I gave him a box of ammo and said "Make some brass".  I'm hopefull this solves the problem.

And for those who are wondering.....

He never experienced this problem before because of old, out of date and lame training.  Slow rates of fire at long distances.  When I updated the training (close range with rapid fire) he noticed the problem.  Heres a laugh.....he's been with the department for over 4 years!!!  Who knows how long the spring had been installed incorrectly!!!

Funny thing is I used just about every check to make sure the rifles function properly, firing pin protrusion, head space go - no go gauge, function checks and a up close and personal inspection.  I would have never guessed some knuckle head screwing up something so simple.

Thanks guys for the good advise!!!  

(Now I'm thinking to myself, 22 other rifles in the department - how many more are incorrect?)

Glad to hear everything worked out and I would have never guessed an inverted spring, sounds like you were thorough and tenacious on your function check.

Yep,

We've had the rifles since 95' and none had ever been done.  Talk about your poor maintainence.

David

Bushmaster master, Master gun smith and will move out to  WY in a heart beat if you ever need a hand.

I think it was the past armorer.  The officer who is issued the rifle is also Army National Guard and he KNOWS better then to take one of these babies part.

Our past instructor/armorer is an ex-Marine (not that theres anything wrong with that..... hehe) and had his own way of running the AR program.

The rifles were bought band new so I really don't think that Colt assembled it wrong......and I know it wasn't me......so that leaves only one person.

But no real harm done..


I agree with you door gunner,  had another officer (guess what .....another ex-marine) removed his hand guards and then the gas tube..phhhhewww....good think I wasn't the armorer then.....he might not have the luxury of a Patrol Rifle now.  Way too much stuff can go wrong in a big hurry if you fuck up one little thing.  Thats why I make it very clear  FIELD STRIP ONLY!!!!!


David