Mod 10-5 Thumb-piece/Cylider Latch

[rswartsell]

I have in my hand a blued S&W Mod 10-5 with a 2" barrel. This was purchased used a few months ago. I shot it extensively yesterday and observed that the cylinder was balky to open, rounds hung up a bit on ejection.

The thumb-piece was bit stubborn to get to the full forward unlocked position. Action displayed minor signs of not being as crisp and free as a Model 10 can be. I elected a soak overnight in "Ed's Red", blow it out with brake-cleaner aerosol can, clean with Hoppes 9 and re-evaluate. I filter the "Ed's Red" back into storage and it is apparent that some old crud was removed. I haven't yet removed the side-plate.

I re-lubricated the revolver and dry fired with snap caps and went through a few reloading drills. A slight but noticeable improvement in double action, a fair amount of lead came out with the cleaning.

The thumb-piece is still a bit tough to get full forward making opening the cylinder harder and slower than it should be. I do not find on Numrich's schematic such a part as a cylinder release spring, but obviously one is employed in operating the thumb-piece. What is the first "usual suspect" for such symptoms?

 

[Jaymo]

S&W calls the cylinder release a "bolt".
There is a small spring and plunger in the rear of it that pushes against the rear of the frame.

I'd take the sideplate off and disassemble the revolver and clean again.
The bolt spring could be weak, broken, or stuck in the rear of the bolt.
Could be missing, too.

How hard is it to push the cylinder center pin forward, with the cylinder open?
It may be gakked up with fouling and/or factory preservative oil turned to varnish.

You'd be amazed how many people buy brand new guns and shoot them for years without ever cleaning out the factory preservative oil.
Every one of my old Smith revolvers was that way when I got them.

The bolt spring pushes the bolt forward, to the unlocked position.
The cylinder center pin spring pushes the bolt back, to the locked position.

I suppose a bent center pin would also be a possibility, also.
A thorough cleaning and prober lubing will tell if that is the problem.

 

[rcmodel]

Maybe packed crud in front if the thumb piece in the slot in the frame it rides in.

Take it off and look in there.

Also make sure the ejector rod isn't loose and backed out.

rc

 

[rswartsell]

Removed the thumb-piece and blew it out, removed any visible debris with a soft rag. Lightly oiled and replaced thumb-piece. I think a minor improvement. Still not 100%. Removed cylinder retaining screw and the cylinder. Cylinder center pin seems OK. I note the ejector rod rides a little heavy on one side when actuated, but no visible bend.

Elected to remove side-plate. Screws removed, rear flush head screw is buggered from previous removal. Used the rubber screwdriver handle to rap on grip frame. Rearmost edges of side-plate raise as expected, forward edges do not. Rap a few more time, and a few more again.

Side-plate is going to be stubborn, I know better than to pry it in any way. What now to coax it free?

 

[rcmodel]

Use a hardwood hammer handle or a hard plastic hammer.

Your rubber screwdriver handle is not transmitting the shock to the frame to pop it loose.

rc

 

[rswartsell]

That did it,

Side-plate is free, hammer block came out with it. Doesn't look bad, Ed's Red obviously did some clean up. Cylinder lock cleaned further and blown out again with brake cleaner. One tiny piece of debris looks for all the world like a piece of paper folded into a tiny triangle (????). Notice on the inside frame surface opposite of removed side-plate, Just under where the mainspring engages the hammer, there are bright scratches from some-ones previous visit under the side-plate?

What was Bubba doing? Anything else to check before lubing and reassembling?

P.S. What do you say about best practices under side-plate lubrication? A drop (Remoil) where?

 

[rcmodel]

I'd put the cylinder back in and try it before completely reassembling the gun.

Also be sure the locking bolt in the barrel lug is beveled off slightly.
If it isn't it will bind in the end of the ejector rod and make opening more difficult.

From S&W armorers manual:


rc

 

[rswartsell]

The bevel is good, did notice on reinstalling the cylinder that the cylinder gap seems very small. I don't have feeler gauge handy to measure and nylon hammer isn't here either (for replacing side-plate) so I'm stopping here to complete later.

Seems right now that I still haven't solved the issue completely, but I am being distracted right now so it's a good place to quit. More later.

 

[rcmodel]

Just press the sideplate on with your fingers!

If you pound it on with a plastic hammer and get the hammer block safety out of place you can very easily spring or bend the sideplate.

rc

 

[BBBBill]

Check for a misaligned yoke, a bent center pin, and loose ejector rod.

 

[rswartsell]

Got it rc, (wouldn't strike the side-plate... thought more of striking the frame to settle the side plate-lack of this hammer was why I was using the screwdriver handle to remove).

The ejector rod isn't loose. Most be Loc-Tited, couldn't budge it with finger pressure. Center pin seems to function normally, should I disassemble the ejector rod, ejector star assembly? How do I check for yoke alignment? BTW guys you are helping immensely. I have gotten to the mid 50's part of my life with little 'smithing skill or experience.

 

[rswartsell]

A bit of background, a young man that I work and hunt with had absolutely no revolver experience. He was a hi-cap 9 baby and we went to concealed carry class together. He became sympathetic with my reasoning for carrying a Colt Detective Special. He did not like J frames for shoot-ability and I shopped for and bought this Mod 10 for him. It is not mine and it's primary function is concealed carry personal defense.

I saw immediately (yesterday) that even though this 10 is great in every other way, combat reload situation needs to be improved. Clark Custom shop is here in town, so I don't wish to go where I shouldn't and the piece is definitely worth a repair.

I may have gotten it with the simple things I trust myself with, maybe not. Either way I appreciate the help.

 

[Old Fuff]

This isn't likely, but remove the thumbpiece after unscrewing the thumbpiece nut, and look for scratches on the sideplate. This would indicate that the thumbpiece was set too low and rubbing.

S&W should still have new thumbpieces, and without question you should find a take-off at www.gunpartscorp.com

To add: Gunparts only has some in fair condition. Try www.brownells.com

 

[BBBBill]

Yoke alignment is checked by removing the yoke from the receiver, removing the cylinder from the yoke (slides off the back), inserting a yoke alignment tool, reinstalling the yoke on the receiver, and closing the yoke as you would when closing the cylinder. The pin on the back of the yoke alignment tool should drop cleanly into the center pin hole in the breach face. If the yoke is tweaked, the pin will either not go in or it will close hard with the pin bearing to the edge of the hole. To straighten the yoke, a nylon or wooden wedge is drifted in to gently bend the yoke barrel up or down as needed. If it is bent to the side, you tap on the yoke with a Babbitt bar or lead hammer to gently move it over to center. It will often be a combination of the two, wedge and Babbitt, and you're only moving the yoke a tiny amount.
DO NOT tap on the yoke without the alignment tool installed. You might crush the yoke barrel.

The #2 is the correct one for a K frame -
http://www.brownells.com/gunsmith-t...ane-alignment-tool-sku080616002-654-2801.aspx

A bit pricey for a one time job, but you may be able to rent one from one of the reamer rental places as the often have other tooling for rent.

The wedge -
http://www.brownells.com/gunsmith-t...s/accurizing-tools/nylon-wedge-prod25429.aspx

Babbitt bars -
http://www.brownells.com/gunsmith-t...-tools/crane-tools/babbitt-bars-prod1250.aspx

 

[rswartsell]

Well I only have a few minutes to work with this tonight and I'm finding just how clumsy I am at repositioning the side-plate. Must not be holding my jaw right.

 

[Old Fuff]

Usually the problem is an out-of-place hammer block. Be careful to position it before trying to seat the sideplate. This is yet another reason I try to fix/lubricate/clean things without having to remove the ^&$%% thing.

 

[rcmodel]

The hammer block needs to be positioned on the pin in the rebound slide, and then slid all the way UP with the top end between the hammer and frame.

The side-plate should slip right back into place then.

rc

 

[rswartsell]

Well this one doesn't, when it came up finally it has a couple of spots where the blue was worn on the outside edges from abraiding (just white spots in the blue, no metal damage) the frame going on and off. I've had it aligned what I think is perfectly a couple of times and these spots don't want to fall into place. I think this requires a bit of patience.

When putting it in place you tilt it a bit to get the tab on the top edge to slip under the frame right?

 

[rswartsell]

Well now, that was certainly a test of patience. Especially just to find that it is still not where I'd want it for a personal defense piece. Further diagnosis and parts replacement will be in the hands of local 'smith now.

I do want to that the gurus of THR for their assistance. I'll post results when they are in.

Thanks again!

 

[rswartsell]

OK so there is good news and bad. Bad news first? The Mod 10 I selected for my buddy from Gunbroker had a crane that was not quite right. It functioned, but I knew it didn't feel "right", it does now.

The good news? This little gem was cleaned to a fare thee well, the crane was replaced by a simpatico local 'smith from a part he had in stock and this afternoon after work I couldn't tell the difference from a new one combat reload drills and all.

Less than a C note by a good bit. The double action is sweet, the reloads as slick as (fill in your own favorite metaphor), and now my conscience is clear giving my buddy a snubby K frame personal defense solution.

I am not a gunsmith and do not aspire to being one. That may contribute to the respect I give the good ones including the ones that routinely help the mechanically impaired shooters on this board.

A last set of questions for our resident gurus;

1. the crane wasn't far out at all, is it possible for a skilled smith to correct (tapping it into spec)?
2. do "donor" (used in spec cranes) parts replacements usually work, or generally a bad idea?
3. passing todays usage test, is the snubby 10 "good to go"?

 

[Old Fuff]

1. the crane wasn't far out at all, is it possible for a skilled smith to correct (tapping it into spec)?

Crane = yoke in Smith & Wessonese.

It depends on how it was misaligned. I suspect (or at least hope) that the yoke barrel (the part the cylinder rotates on) was sprung, in which it can be corrected. If otherwise, I need to know more.

2. do "donor" (used in spec cranes/yokes) parts replacements usually work, or generally a bad idea?

You were lucky because the yoke is individually fit to a particular frame. That's the reason both it and the frame have an assembly number. You have a better chance with unnumbered parts such as lockwork, and less so with sideplates, cylinders and barrels.

3. passing todays usage test, is the snubby 10 "good to go"?

It sounds like your gunsmith was on the ball, and had the right tools to do what was necessary. I'd say it's probably good to go.

 

[BBBBill]

Yokes can be straightened with the right tools and the knowledge of how to use them.
Donor parts can be fit/re-fit..... sometimes. Again, the correct tools and knowledge required.

Here's hoping that the smith knew how to fit, had the tools, and checked for proper cylinder/barrel gap, alignment, endshake, and head space.

 

[gamestalker]

I had a beautiful 10-5 that needed a new main spring. But the smith who unnecessarily took the side plate off, pryed it, he warped it horribly. And if that wasn't enough, he then tightened the screws down while the block was not aligned, warping it yet again. He also mangled the screws, and deeply scratched the plate. Then he claimed it was already in that condition when I brought it in, liar.

It was so badly destroyed that the action wouldn't even function when I got it back. So after a bunch of denial, I just grabbed it from him and went home. I flattened the plate out at home, and then ended up having to shim it to get the action to function smoothly. It's now ugly, but at least it functions nicely once again.

This was one of 3 very bad experiences, with 3 different smiths that didn't know anything about wheel guns. I now do all my own maintenance on my wheel guns, I'll never trust another yellow pages smith again. I had seen his booth at the local gun show on previous occasions, so I assumed he was capable, reputable, and accountable, wrong!

Sorry about hi jacking the thread.

GS

 

[1KPerDay]

That's the kind of story that keeps me from sending my guns to a smith. I have a few that need some work but there they sit.

 

[BBBBill]

Unfortunately, there's no requirement to provide proof of competency before hanging out a shingle.