model 10-5 cylinder stop issue

[CZguy75]

Alright folks, got myself an interesting situation. Just picked up a model 10-5 K frame as a project gun. The finish is ugly and I have been wanting to try rust bluing, price was right, so I bought it. Anyway, the gun shoots wonderfully well. I took it apart to clean untold years of gunk, sweat, and oil out of it before shooting it. I reassembled it and went to the range and shot 80ish rounds through it without an issue. Brought the gun home, wiped it off, and put it up. A few weeks later I pick it up and go to dry fire it and it starts intermittently hanging up. Examination revealed that the cylinder stop will drop down, then immediately spring back up before the hand pushes the cylinder up, locking it. I tried it DA and by cocking the hammer and get the same result. This happens about 30% of the time now.

I know that the cylinder stop is "timed" off of the front of the trigger. I just dont know how to go about fixing this. Do I need to be looking into a new cylinder stop, or something else? Anyone else ever had this problem? Thanks ahead of time for the help.

 

[MrBorland]

hmmm....

Open the cylinder and look at the ratchet - I can't recall on the 10-5 - are there 2 little pins holding the ratchet from twisting? If there aren't 2 pins, are there 2 holes? IOW, is the ratchet able to twist while holding the cylinder?

If the sideplate's off, how much "meat" is between the trigger & stop (red arrow)? Is the stop able to slide aft like in the photo (yellow arrow)?

 

[MrBorland]

One other thought: when it locks up, see if the trigger is fully forward. Give the trigger a push forward & recheck.

 

[film495]

never seen this, but if the sideplate is off work the action and observe how the parts function. whatever holds the stop is letting it go too early, so - maybe something is just off or worn, or a spring is missing or gunked up or stuck. is the stop actually going down all the way? maybe something is preventing it from locking into whatever is supposed to hold it until it releases and pops up. Maybe it just isn't making it there.

 

[CZguy75]

I know for sure that the stop will fully drop. I can actually hold the trigger at a certain place early in its travel and the stop will fully drop and stay dropped.. pulling the trigger further rearwards will see the stop springing upwards before the hand pushes on the pawl. I will check the engagement this afternoon.

 

[UncleEd]

Trigger sluggish or soft in its return to reset?

Trigger return spring cut or original replaced?

Clean out trigger return housing spring channel.

Put in a stronger spring.

 

[MrBorland]

I know for sure that the stop will fully drop

Probably not an issue with the trigger return, then: As the trigger returns, the 1st click you hear is the hand engaging the next ratchet in the ejector star. Pull the trigger after the 1st click, and you'll find the gun locked: That's because the hand is pushing the cylinder, but the trigger hasn't re-engaged the cylinder stop bolt, so the cylinder's still locked in place.

The 2nd click on the return is the trigger moving past the cylinder stop bolt. You can actually see the stop bolt move at this point. Pull the trigger now, and the cylinder will turn without the hammer lifting because the DA sear only re-engages with the 3rd click.

Pulling the trigger at any point before the 3rd click (i.e. full reset) are all known as "short-stroking the trigger".

None of these symptoms seem to apply, so I’m less enthused about it being a trigger return issue (though it’s never a bad idea to make sure the trigger on a well-used revolver is returning as it should).

 

[MrBorland]

BTW, I don’t know how much you know about getting inside a S&W, but there’s a right and wrong way to pop the side plate. Best read up on it. Also, de-tension the mainspring before you pop the plate - and if you haven’t de-tensioned it, definitely don’t cycle the action, lest you bend or break the hammer stud.

 

[5-SHOTS]

First of all I would check that I have not overtightened the side plate screws. In any case you will have to remove the side plate to check if the small spring of the cylinder stop is positioned correctly, is clean and works correctly. I would replace it anyway. Then I would check the cylinder stop itself and the rectangular hole from which it emerges, searching for excessive wear or dirt or burrs. However, I would also replace the cylinder stop, perhaps at that point with a slightly wider one to improve lock-up. Also check the status of the cylinder stop pin. When you close the side plate again you will tighten the screws starting from the central one and finishing with the one closest to the cylinder stop. First you will screw the screws until they reach the end but without tightening them completely, then you will tighten them in the order I told you but without overdoing it. Better to use a little Blue Loctite than tighten the screws to death. I don't know how else to help you.

 

[CZguy75]

ok, so I got around to popping it back open. The cylinder stop is pretty sloppy on the pin wobbling rearwards and vertically. everything is clean of debris and gunk. I do not think there is enough engagement for proper function.

 

[Col. Harrumph]

Looking at your above pic, CZ, I see a flat spot on the part of the trigger that bears on the cylinder stop (compare to MrB's pic). That's an odd place to see much wear as there's very little stress on that edge; my guess is that Bubba got in there before you. If I'm right, the obvious fix would be to replace the trigger... but maybe a better idea would be to dab some metal on the stop's mating surface, if ya got the TIG skillz.

 

[Old_Grouch]

It may be the lighting, or the angle the photo was taken from but something doesn't look right to me with the positioning of the cylinder stop spring. It looks to me like it's pushing upwards too much.

BTW, kudos for identifying the part as a cylinder stop and not a cylinder "bolt" as I've seen several do recently.
For anyone who is wondering, there is a part called a bolt in a S&W revolver. The bolt is what is pushed forward by the thumbpiece to unlatch the cylinder.
(sorry, just one of my pet peeves)

 

[MrBorland]

I see a flat spot on the part of the trigger that bears on the cylinder stop (compare to MrB's pic)

something doesn't look right to me with the positioning of the cylinder stop spring. It looks to me like it's pushing upwards too much.

Yup - the trigger “nose” looks a bit flat. Before you try replacing the trigger, though, I agree something looks off with the spring. Notice in the reference pic, the top of the stop is clearly visible above the frame, but not in your pics. If the stop were above the frame, the geometry of the spring might look more normal. OTOH, the spring (and it’s seating) might be the reason the stop’s not protruding through the frame, so I’d check that the spring is seated correctly.

 

[CZguy75]

I will tear back into it and get better pics of the trigger nose and where it meets with the cylinder stop. I will also check and make sure the spring is correctly seated while im there. As it is in my last picture, the angle doesn't show the stop being up, but it is protruding from the frame. And yes, the face of the trigger nose is almost completely flat on mine. It does not have the same profile as the one in Mrborlands picture. Thank yall for the help so far!

 

[MrBorland]

I should caveat that not all S&W triggers were designed identically (and that I'm no gunsmith ). The the trigger below looks more like the OP's. The OP's trigger nose might or might not be too flat, but the bigger point is to try cycling the action (with mainspring tension reduced) to see where the issue is - it might (or might not) be that the trigger is sliding past the stop too quickly, and that might (or might not) be because the trigger nose is too worn. Try putting the cylinder back in, and check also for slop in the hand, as well as for the aforementioned ratchet.

 

[5-SHOTS]

That's exactly right. When ordering any spare parts you must be sure to order the right ones, i.e. the spare parts suitable for the model number engraved in the frame (including the number after the dash) and readable when you open the cylinder.

 

[CZguy75]

Maybe this pic will be better. I did fiddle with the spring angle and had good results from it. I figure it cut the stoppages by 75%, but it still does hang sometimes. At this point I am going to order a spring kit for the ol gal and see if it improves it any further.