Hammer jamming on 10-5

[Furdog]

Just bought a real nice 10-5, looked like it has been shot very little. The gun is DAO with a bobbed hammer. I suspect that is not original. First range trip was a disaster, would lock up almost every shot, finally couldn't pull back the hammer.

Without ammo it dry fires OK, feels like a slight drag on one cylinder, but will cycle. When I first tried it, it jammed empty. I took it apart, checked for any roughness, and replaced springs (rebound spring was very weak). After reassembly it seemed 95% improved.

Firing live ammo it still jambs. The gun will normally fire a shot or two, then you can't pull the trigger, it is totally locked up.

Firing pin and firing pin bushing look fine. No roughness on hand or cylinder ratchet. Ejector rod is tight and straight, yoke is not bent.

I am at a loss! Who has an idea?

Thanks

 

[Jimmyjones]

I've had the cylinder stop spring give me similar issues. Only acted up during live fire, not dry fire.

 

[bgrafsr]

Check under the extractor for debris that may not let the extractor lie flush.

 

[armorer951]

A short list of possibilities include: Cylinder/yoke alignment, extractor rod loose, bent or improperly fit, dirt under extractor, burr on breechface/hammer nose bushing, front and/or rear gauge out of spec, ammo not seating properly in the cylinder, internal parts binding on sideplate, alterations/damage by previous owner, etc. Other members will post additional ideas.

 

[big brother]

One other possibility that I have encountered lately. Man had some ammo that the rim diameter was too big and the ctg would not go into the recessed cylinder all the way. Some went in; some went almost in and some just sat on top. The gun may not be the problem. Look carefully when you load the cylinder.

 

[canvsbk]

Cylinder to barrel gap too tight?? Had that on a 686, would lock up after a few shots.

 

[HeloMt]

I would check out the cylinder stop. If someone DAO'd the gun, they were inside and might have changed the angle on the cylinder stop bevel to the point it won't release the cylinder before the hand is applying rotational pressure to the cylinder, effectively tying the gun up. It is usually worse with ammo in the cylinder because the ammo will not allow for the usual play between the extractor and the cylinder via the pins and the spline. The hand will be more positive with ammo in place because it forces the extractor and cylinder to act as one instead of seperate pieces.

 

[Furdog]

Update on jamming 10-5

After checking most of the above suggestions, and going to a stronger rebound spring, I thought all was well. Checked yoke, tightened extractor, double cleaned everything. Gun dry fired with cases in cylinder functioned fine.

Back to range. Fired OK for about 24 shots then gave suggestion of stiffness, a few rounds later locked solid. When it jammed the cylinder was locked, and hammer half way down. There is no end shake and the barrel cylinder is not real tight.

Thanks for all the ideas so far. Anybody have another idea?

 

[Alk8944]

Take it to a local gunsmith who understands S&W revolvers and let him examine it hands-on.

 

[tputto]

A broken hammer stud gave me somewhat similar issues. The sideplate may keep it in place but it will allow the hammer to wobble and lock up the mechanism. Yours could be cracked and not completely broken off just yet.

 

[Furdog]

Hammer stud is one I hadn't considered, I will look closely at that. It has to be something that can misbehave on and off. Reason i haven't taken it to a gunsmith yet is I enjoy tinkering, and this gun isn't critical. Thanks for everybody's help.

 

[Stephanie B]

Also, make sure that the recoil shield is true. If the gun was dropped in such a way as it landed on the right-hand recoil shield, that can act to bind the hand and jam the gun.

(No, I'm not going to say how I learned that this can happen. Trust me on this. )

 

[Philblack]

Are your hammer and/or trigger tight ? A "floating" (left to right) trigger on its axis could cause this...

 

[Furdog]

Don't know the answer to that one. When I tear it down again I will check the hammer stud, recoil shield and the trigger slop.

Thanks for all the help everybody. We have to be getting close!