Model 48 Problem

[Gazz]

I recently came across a model 48 in like new condition cosmetically that has a problem. It will rarely function in DA mode but usually in SA mode. When I try it in DA, the trigger will move slightly and the hammer will come back maybe 1/4" and then everything stops hard. It occasionally does the same thing in SA mode. I took it apart and found the insides to be very dry so I removed everything , applied lubriplate and put it back together and it still does the same thing. I have tried operating it with the sideplate off being careful to keep the rebound slide in place to see if I can spot anything but nothing obvious is jumping out at me. Does anybody have any ideas what may be the problem?

 

[armorer951]

Sounds like the cylinder stop may me late....or, in other words, not being pulled down out of the cylinder stop slot in the cylinder
soon enough. Could be due to wear on the hook of the trigger or the bevel on the cylinder stop....or perhaps improper fitting or alteration of these areas.

 

[Gazz]

I looked at it again today and that is exactly what is happening. The screw heads for the side plate were lightly chewed up so someone has been inside before either to try and fix it or to create the problem. I have quite a few S&W parts but I an guessing I don't have any peculiar to the 48.

 

[armorer951]

If the bevel on the cylinder stop is too short (worn or altered), a competent gunsmith should be able to fit a new one. Be sure to ask him to have a look at the hook on the trigger to be sure it's not worn or altered as well. You may have to repplace both parts, depending on the damage.

K series cylinder stops are still available. The OEM part number is 03128, for the carbon steel stop, and 07046 for the stainless steel part. Either will work fine. I would probably replace the cylinder stop spring as well.

Numrich has the part you need if you can't find one in your area.
Cylinder Stop Gun Parts | 308330 | Numrich Gun Parts

If you don't have a competent, trusted smith in your area, you could contact S&W Customer Service 1-800-331-0852.

 

[armorer951]

If you are unable to find an OEM stop let me know, I can send you one.

 

[jimmyj]

Cylinder stop spring ?

 

[Hondo44]

Yes, the one inside the frame in front of the cyl stop.

 

[Protocall_Design]

Sometimes a broken trigger pivot pin can act like that.

 

[Gazz]

Thanks for all the replies and offers! I happen to have quite a good supply of S&W parts as I bought out the estate of a gunsmith some years ago and in the pile of parts was what looked to be a new and unused K frame trigger. There were also some cylinder stops in there too but I thought I would would try one part at a time so I installed the replacement trigger and it works fine now. The side plate screw were slightly buggered up so it was apparent that somebody else was inside before and I am guessing they tried to do a little "smithing to improve" things but failed. Probably why the revolver is in such nice shape finish wise.