Trigger stacking

[denfoote]

What is it??
If you have it, how is it cured???

The reason being is that my Taurus M85UL will sometimes cycle and when I squeeze the trigger for the next shot, it is real hard to pull, followed by the usual bang!! The trouble is that it does not go through the usual travel!! it seems to fire at the start of the pull!!! Sort of like a hair trigger from hell!!!!!
It seems to be an intermittent problem as far as I can tell!!!

I really like this revolver. I put it through Jim's revolver test an found that it is in time, the cylinder gap is .003", there is no lateral movement of the cylinder , only a slight rotation during lockup, and it is extremely accurate in it's expected range!! The only thing is this nagging trigger problem!! :banghead:

Any advice would be appreciated.

 

[Old Fuff]

Something is seriously wrong. If the trigger is in the forward position the transfer bar shouldn't be high enough to cover the firing pin. I suggest you:

1. Remove the sideplate (if you know how) and inspect the action for more clues.

2. Or return the gun to Taurus and let them find the problem and correct it.

 

[denfoote]

!!!!
That's what I half expected!!
OK. Back to the womb it goes!!! :banghead:

 

[Old Fuff]

I'd try to help you more, but what you describe is most unusual and without being to disassemble and examine the lockwork there isn't much more that can be done. There is a possibility of a broken hammer or trigger pivot, and if that's the case the factory will have to fix it. The little 85's are generally very reliable so I'm a bit suprised about what is going on.

 

[JohnKSa]

That's not trigger stacking, that's what's called busted...

Stacking means that the pull weight gets noticeably stiffer toward the end of the trigger pull.

 

[Jim March]

Agreed with all of the above. That gun is currently unsafe. It must be checked by a competent gunsmith or go back to the factory.

I recommend against loading it or firing it again until this happens.

 

[denfoote]

Taurus M85UL

It's all boxed up and ready to go!!

 

[Old Fuff]

I don't wish you any bad luck, but when you find out what happened please post an update. I really wonder what it could be.

 

[denfoote]

I'm not sure that I will!!
Taurus, as I understand it, is not in the habit of providing detailed information on what they actually do to your gun, other than to declare it fixed!!

I'm shipping it through Mandall's in Scottsdale.
When they get it back, I'll ask them if Taurus sent anything with the returned gun.

 

[Sean Smith]

It has pretty much all been covered.

1. Your gun is badly busted.
2. Stacking is when the trigger pull weight increases the further back it is pulled.
3. And to answer how to fix #2, a trigger job will fix it. In most revolver designs this is fairly simple and cheap, in Colt Pythons fairly eloaborate and expensive.

 

[WhoKnowsWho]

Stacking... see Walther P22 Double Action trigger when brand new! Geez that thing was tough.

 

[Old Fuff]

>> 3. And to answer how to fix #2, a trigger job will fix it. In most revolver designs this is fairly simple and cheap, in Colt Pythons fairly elaborate and expensive. <<

Actually correcting “stacking†in a Colt Python isn’t difficult or (shouldn’t be) expensive. These revolvers have a “V†shaped mainspring and sometimes toward the end of the trigger cycle the two leafs come together and bind. Reforming the spring, or removing a small amount of metal from the top of the rebound lever should eliminate the condition. Other related issues may require more work, but on a Python they should have been attended too in the first place.

Small-framed revolvers with coil mainsprings are harder to deal with because the pressure on the hammer is mostly linier – it gets steadily stronger until the hammer is released. With these changing the spring for a different (but not necessarily lighter) one may help, but it’s usually better to work with the trigger return spring rather then the main spring.

Smith & Wesson K-frame and larger revolvers have a single leaf mainspring, and it seldom stacks unless someone unwisely messes with or shortens the tension screw. Because of it’s design the hammer tension actually lowers during the last part of the hammer’s cycle. It is not coincidental that this company’s products have a long-standing reputation for smooth non-stacking actions.

 

[bountyhunter]

It sounds like a problem with the DA sear. A revolver pulled DA has two stages: the trigger nose lifts the hammer using the DA sear for about the first 1/3 of the way back. Then, a different part of the trigger slides under the hammer and lifts it the rest of the way until it lets it drop. This sounds like maybe the trigger slips past the DA sear letting the hammer fall before it picks up the next sear face... which is very dangerous.