Double Firing 1911-derivative

[Cowboy_Dan]

My brother recently bought a previously owned Para-Ordinance P13.45. For thise of you not familiar with it, it's basically a 1911, but it takes a double-stack magazine. Today we took it to the range to test it out. It started fine, but near the end of the first magazine it fired 2 rounds when he only pulled the trigger once. We weren't sure at first that this happened because we found a live round behind him. We thought maybe it ejected a live round somehow since stranger things have been documented. That magazine finishehd out without incident.

I had the 10-round magazine loaded to try it next. Insert magazine, chamber a round, pull trigger, bangbang. Black rifle guys were reloading at the time this time, so second bang wasn't them. I ejected the magazine and emptied the chamber and the magazine into my hand. Look where brass has been ejecting, 2 empties. I reflect that the recoil seemed to lift the gun higher than expected.

So, what is likely happening? The gun inconsistently shots once and twice. Is there anything we should test to help discern the problem? I was thinking maybe load a few magazines alternating live rounds and dummies so it can't fire twice if it wants to, but we can tell when it would have.

[M-Tecs]

Most likely a worn, damaged or incorrectly modified sear. When you release the slide on an empty chamber on a 1911 you should hold the hammer down so it can't follow down. If it follows normally it will stop at the halfcock notch however doing it repeatedly will damage the sear but in this case try releasing the slide on an empty chamber. If the hammer follows down some trigger work is needed.

Also milking the trigger can cause doubling.

[44man]

Too light a trigger. I built one for a friend that we shoot fine, one shot at a time. Another friend always gets a double. John wanted the lightest trigger I could make and me and him can not make it double but Pete can not get one shot, always two. The 1911 is tricky. Wear could be a factor but so is the shooter. It is why most guns have such bad trigger pulls.

[John Taylor]

ATF will have you in jail for owning it.

[OS OK]

My .02 cents bet on a modified sear…polished and lost the crisp edge…or a shooter that is heavy fingered on the trigger with an auto.
My Para 14-45 has never done that but that does not count for anything but my pistol…thats all.
.02 cents on the sear.

[cwheel]

Had that happen couple of times when building 1911's. Most likely a disconnector fitted improperly. Get a copy of Jerry Kuhnhausen's book " Colt 45 Automatic, a shop manual " He goes through proper fitting and testing a disconnector. On a side note, when testing a 1911 after repair or build, load a mag with only 2 rounds, fire the first shot, check the chamber for the second live round. This is a standard procedure until the disconnector proves itself under fire. Firing full auto with a 1911 happens very fast, first couple of times I didn't catch it. As John Taylor above, ATF is hot happy with this. However it is a " Malfunctioning firearm " that is broken unless intentionally modified to fire full auto. Still not legal, but malfunctioning is much easier in court.
Chris

[M-Tecs]

ATF is hot happy with this. However it is a " Malfunctioning firearm " that is broken unless intentionally modified to fire full auto. Still not legal, but malfunctioning is much easier in court.
Chris

Agree 100%. Has the ATF charged anyone for a doubling firearm? I was aware of a case in the 70's that the ATF lost do to the lack of intent. Haven't heard of one since.

[Cowboy_Dan]

I just tried closing the slide on an empty chamber. From the locked back position with no magazine inserted the hammer stayed put 3 out of 3 times. I could try it again with a magazine inserted, but I can't see how it would make much of a difference.

As to the trigger, I'm not sure what "milking it" means, but we were pulling it our "normal" way. The trigger isn't nearly as heavy as the one on my Tokarev, but it's also not a hair trigger by any means. There is a bit of wiggle to it (with the hammer down at least). Also to 44man's comment, it doubled for both of us, so I hesitate to blame the shooter-trigger interface.

Oh, and the Feds aren't the only reason we're worried about this. We really don't want the issue to progress to the point that it slam-fires the whole magazine. We really want to just nip this in the bud. However, I don't forsee BATFE hunting us down over a malfunction which we are seeking to prevent.

[M-Tecs]

Milking the trigger in a rifle and a pistol are somewhat different. With a pistol the term generally applies to squeezing the whole hand. With a rifle it is also called feathering. In both cases it can lead to a bump fire.

Good discription for a rifle here.
http://www.thehighroad.org/archive/i.../t-788861.html

Since it doesn't follow down and you don't think you are bump firing it you may be in need of a trigger job.

A good smith can do a glass crisp 2 1/2 pound 100 % reliable trigger on a 1911. Most general smiths are not very good on 1911 triggers.

[bosterr]

Besides an improperly modified or worn sear, it could also be the sear spring bent too far to get less tension for lighter trigger pull.

[AggieEE]

+1 on the worn/improperly fitted sear. I've also seen a sloppy trigger cause the problem. If you don't squeeze the trigger all the way back to the stop and force the disconnector to dis-engage the trigger will bounce just enough to trip it again. Properly fitted parts and your good to go.

[country gent]

I would start with the flat spring under the grip saftey, the 3 legged one. look for worn edges modififications to it and broken cracked fingers.Also check the firing pin spring for length tension. The sear and hammer nothes need to be checked for improper fit and chiped areas. Cylinder and slide shop sell a drop in kit thats 3 1/2lb pull and should drop right in. It may be a combination of springs worn parts and trigger pull techniuque. It shouldnt be to hard to fix. If new parts are installed then you might want to fire 200-300 rounds as is before having doing a trigger tune up.

[44man]

It will not go full auto, just 2 rounds is all we ever seen. And only one person. Nobody else can make it double as hard as they try.

[square butte]

Could be a limp wrist hold on the one who it doubles on

[nicholst55]

Agree 100%. Has the ATF charged anyone for a doubling firearm? I was aware of a case in the 70's that the ATF lost do to the lack of intent. Haven't heard of one since.

Yes, there is a fairly (in)famous recent case where a guy had an AR-15 that he knew was doubling, and he loaned it to a friend. Not sure of the specifics, but the ATF became involved with the friend, and ended up charging the owner with possession of an unregistered machine gun, and illegal transfer of same.

[M-Tecs]

I would love to read more about the specifics. You have anymore details? If true every smith that receives a doubling firearm for repair is recieving an unregistered NFA item.

[Jim_P]

While I was in Germany with the Military, a friend bought a Glock from the local Rod and Gun club. He took it to the range for the first time and it doubled on every pull of the trigger. The RSO was going nuts telling him not to double. He finally told the RSO to try it himself as he wasn't doing it.

Brought the gun back to the Ron and Gun club and they returned it to Glock. Seems it was a pistol originally destined for the Bolivian Police. No idea how it got to an American R&G in Kaiserslautern, Germany, but it did. He got a new one back from Glock that only shot once. I told him he should have kept his mouth shut and bought a second gun...

[DCM]

Last time I checked it had to discharge "More than 2 rounds with one pull of the trigger" to be considered full auto.
It May have changed but folks with old doubles better CYA if so!!

[1_Ogre]

Jerry Kuhnhausen's books are the 1911 Bible. I've built up a few 1911's in my life, and I "NEVER" do one with a trigger under 4lb, NEVER. IMHO, except for BullsEye it's going to be a problem. I've refused trigger jobs where the owner said "I want a 1-2lb trigger", I turn them away. A good trigger job at 4 to 4 1/2lb done properly feels like a 2lb trigger job.
I'd check the disconnector/sear engagement points and look closely under magnification. If they are worn/ramped/rounded/or at an angle, replace them. Also check for dirt in the firing pin channel. Dirt build up there, I've seen space the firing pin out too far and when the slides dropped it goes into auto fire.
Just some observations from an old guy

[lightload]

This may be bump firing. Is the trigger itself light weight like aluminum or polymer, and is the spring section that forces the trigger forward adjusted to provide suitable forward motion?