Kimber: Unintentional auto double taps

[Picknlittle]

A friend of mine recently purchased a Kimber custom sumpin, sumpin, sumpin .45. It's a beautiful gun, very accurate, very comfortable to shoot but it has one disconcerting feature. On occasion a trigger pull results in two and maybe even three shots. It happens so fast it sounds more like a burp and apparently happens so quickly the muzzle doesn't even have time to rise. The bullet holes impact so close together they appear as one slightly enlarged hole.

Any ideas as to why this is happening. I think the trigger is between 1.5 and 2 pounds pull.

 

[Spartacus451]

First get a trigger pull scale and check to see if the trigger is really that light. A factory Kimber isn't supposed to come with the sear spring set that light.

Second check and reset the overtravel screw. Back it in until it stops releasing the sear and then back it out until you can feel the hammer fall without the sear touching the half cock notch. Then back it out a smidgen more and you are done. Loctite it for good measure.

 

[Jim Watson]

This is somewhat dangerous, if it ran away for the full magazine, there would be no controlling it and the last of the mag would be launched at a high angle as the muzzle came up in recoil.

There are also feds who would prosecute it as an illegal automatic weapon. They have run in at least one guy for owning an AR that would shoot full auto due to misfit or wear.

Get it fixed. It might be something as simple as a weak sear spring or too close setting of the trigger overtravel screw per adweisbe. It might be due to wear or damage to the hammer full cock notch or the sear tip. But it isn't right and will give him nothing but grief.

 

[krs]

In a Kimber it could be a broken sear, but in any case I agree with adweise (edit: and Jim Watson who must have typed while I typed slower) that the trigger is too light for safe operation.

Your friend bought someone's lousy trigger work probably.

I'd also submit the possibility that you are mistaken in thinking that all rounds went to the first hole. It's far more likely that they went upward off your target into the netherland of innocent civilians.

This needs to be fixed. Don't load more than two when testing the fix.

 

[Picknlittle]

Your friend bought someone's lousy trigger work probably.

It's a brand new custom Kimber.

I'd also submit the possibility that you are mistaken in thinking that all rounds went to the first hole.

Fresh targets, fresh mag, fresh figure eight holes. This gun has surprising low recoil,...not non-existent, but very low and controllable. This happened four times, twice to the owner, once to me, once to another shooter. The holes were never more than 1 inch apart.

I absolutely agree it's dangerous and should be fixed. That's why I mention it. I just wanted to see if it might avoid a trip back to Kimber. Steve tells me the trigger tests at 1.8 pounds per his scales. It's light for me, but it's not my gun.

 

[rcmodel]

1.8 pounds is a defective trigger on any 1911, I don't care who made it.
There is no way to keep a 1911 hammer from following down with a 1.8 pound factory hammer & sear, period.

That the safety notch doesn't catch the hammer indicates the sear is either toast, or the sear spring, one or the other.

With factory trigger parts from Kimber, it should be at least 3 1/2 pounds, or more likely 4 1/2.

I also am at a loss as to how you can keep three shots on a target with the holes all close together.

I have had a 1911 go auto with a full mag of GI hardball, and there were holes in the range roof when it ran dry!

Regardless, in it's present condition, the gun is very unsafe, and should not be fired until it has been repaired properly.

rcmodel

 

[krs]

Fresh targets, fresh mag, fresh figure eight holes. This gun has surprising low recoil,...not non-existent, but very low and controllable. This happened four times, twice to the owner, once to me, once to another shooter. The holes were never more than 1 inch apart.

Guns don't have recoil, cartridges make guns recoil and a load so light that it didn't cause muzzle rise would also not cycle a 1911 pistol.

You might have had figure eight holes, but that's most often caused by keyholing which is a separate and interesting characteristic of this so called brand new Kimber with it's 1.8 lb trigger.

What's the difference WHOSE lousy trigger work he bought? Kimber's or Bubba's, it's all the same lousy trigger work.

 

[1911Tuner]

a load so light that it didn't cause muzzle rise would also not cycle a 1911 pistol.

Sure it would. When a 1911 goes full-auto, it's so fast that the gun doesn't have time to move very much.

I've had one do it, and ...even holding the gun in one hand...all 7 rounds were gone before the gun moved more than about 6 inches off of a 16X12 inch steel plate at 21 feet. Four out of seven hit the plate.

Gripping hard with both hands resulted in 6 out of seven hits.

The gun moves slightly up, and mostly to the right. Figuring the starting point as the center of a clock's face, it heads toward 2 O'Clock.

You may verify this by shootin' a PM to member Ken Rainey. It occurred with his Kimber in June, 2003.

 

[rcmodel]

Seems your mileage may vary.

That certainly wasn't my experience on the 5th. Army AMU covered range in 1969.

I agree with the heading for 2:00 O'Clock part, but with GI hardball in a National Match gun, mine ended up almost 45-50 degrees vertical from a one-hand target stance.

rcmodel

 

[1911Tuner]

Seems your mileage may vary.

It will. I'm fairly big with large, strong hands. My body and shoulder mass is harder to move, and grip strength is subjective. What may be a firm grip to you may be a light grip to me...and vice-versa.

FWIW, Ken and I were shooting standard hardball and equivalent reloads that day...so it wasn't underpowdered ammo.

 

[Geno]

My Kimber Warrior had a tendency to do double-taps without me intending to do so. It did not malfunction, rather the trigger was so light, and the reset was so short that it would sometimes launch two rounds where I intended one. I posted about this fact a few times here at THR, and that for this reason, I did not feel comfortable carrying this Warrior for CCW.

For what it's worth, my Colt Gold Cup Trophy resets very fast. After firing a round, I simply have to release the trigger about 1/64th of an inch and it's reset. It, however, has a stiffer trigger than the Warrior had.

 

[N1150X]

There are also feds who would prosecute it as an illegal automatic weapon

I know it sucks but its true. Get that puppy fixed or your friend will spend some time in the big house if he gets caught

 

[Kruzr]

What adweisbe said......

I've just seen this on a new 9MM Kimber. It turned out that the overtravel screw wasn't adjusted at the factory. I was able to turn it two full turns before the hammer wouldn't drop. I backed it out half a turn, checked for rub and it was fine.

On Kimbers, and I don't know if the mag catch is thinner, but with the overtravel screw backed out on the factory trigger, it puts pressure on the sear spring and relieves the pressure the finger is exerting on the sear making the gun double. By that time, the shooter has usually released the trigger so there is no triple.

However, if the trigger is truly 1.5 - 2 lb rather than 3.5 - 4 lb on a new Kimber, I'd say the sear spring needs a tweak. I've never seen a bad sear on a new Kimber but stranger things have happened.

 

[Picknlittle]

Thanks for the info guys. From the comments here and some additional research I have learned a couple things.

1. A critically adjusted trigger requires a firm follow through to the stops to avoid a bouncing finger. As I think back to the experience I realize the gun was so smooth that a firm grip was likely where my discipline stopped. I'm pretty sure I allowed my finger to get lazy. This is a gun for a more experienced competitive shooter. Not one I'd carry for defense as is. I'd also be reluctant to put it in someone else's hands without fair warning to that affect.

2. It's best to have a custom gun built for the shooter instead of buying a custom gun expecting the new owner to understand it's intricacies. There is really noting wrong with this gun,..it's the lack of experience and shooting discipline that doesn't meet the gun's requirements,....not the other way around.

This principle holds true is all finely tuned tools. Acoustic guitar players familiar with Tony Rice's herringbone know that in the hands of a mear mortal, Joe average guitar player, the guitar buzzes and is pretty unimpressive in terms of volume and tone. The guitar is built for the master's hands with extremely low action and precious little neck relief. Tony's touch makes it come alive,...in my hands, it might well be a plywood junker.

Thanks for the insight guys.

 

[Spartacus451]

A NIB stock Kimber should not have a 2 pound pull and I would not trust it to have been correctly adjusted to function as such. I would only do it with the lightest weight trigger possible (STI with polymer shoe) and a sear spring designed to be adjusted to low weights and hammer sear engagement needs to be perfect on both sides.

I am not very trusting of other people's work especially the ones that work for a major manufacturer of any kind.