Repairing Endshake

[Confederate]

On another thread, dfariswheel discussed endshake, the condition in a revolver of having excess lateral (horizontal) play in the cylinder.

With the gun UN-COCKED and the action at rest gently push the cylinder forward and hold it there.
Use an automotive feeler gage to gage the barrel/cylinder gap.
Push the cylinder to the rear and hold it while you gage it again.

Subtract one measurement from the other and that's how much cylinder end shake you have.

He then gave these instructions for repair of Smith & Wesson revolvers only. They refer only to S&W, not Colt.

For S&W revolvers, the end shake cannot be over 0.006".
Colt's are much tighter specs with the maximum allowed being 0.003".

S&W revolvers can have end shake corrected by three methods.
1. Trim the rear of the cylinder yoke to true it up, then install greased hardened stainless bearings.

2. Stretch the yoke barrel by inserting a hardened steel stud to act as a support, then gently peen the yoke barrel to stretch it.

3. Use a special tool made from a tubing cutter to stretch the yoke barrel.
The tubing cutter has the hardened cutting wheel rounded off to a round, non-cutting edge. The tool is used on the rear of the yoke barrel. Instead of cutting a groove, the tool rolls a round groove in the barrel, stretching it.

My question is, is this procedure something only a qualified gunsmith should do, or can it be done by an end user (pun not intended...well, maybe a little)? If a user can do it, what tools, exactly, would he need. And if it's something only a gunsmith can do, what's a fair price?

Also, is there a book that explains simple gunsmithing chores like this?

As it stands, I'm more likely to have a gunsmith fix it, unless someone encourages me.

Thanks for any replies!

 

[texagun]

I've repaired endshake in S&W Revolvers by using shims sold by Brownells for the purpose. The Smith and Wesson Revolver by Jerry Kuhnhausen explains very well how to do it. Instructions also come with the shims if I remember correctly.

 

[Confederate]

I made a shim out of a washer that I bought at Home Depot. I used a file to file it down in shape. Since it was a bit too small to fit, I used a file to open it a bit and since it was too thick, I put the shim against a flat file and filed it down.

The result is that it doesn't look that great, nor does it seem all that strong, but the endshake is gone and everything is solid.

But still, I'd like to improve the quality of my work. The gun itself is a small Rossi 511. I've been quoted a price of $50-80 for repair. The gun is a .22LR. I have a number of rubber washers that fit perfectly, but I strongly doubt whether they could survive the heat and flame coming from the barrel gap.

Does anyone know of a place I could get an assortment of various washers all thrown together? That would be my best bet. I used my calipher to get me to the closest washer at the hardware store. Still, I'd like to have a bunch of various shims of different sizes.

Thanks, texagun!

 

[MCgunner]

I also understand Brownells sells a "crane stretcher". Someone with more knowledge can bust in here. I looked it up, seems like the tool was 30 or 40 bucks. Would work for most brands and models. The shims from Brownells are only for Smiths in J, K, and L frame IIRC.

 

[Master Blaster]

Get Jerry Kuhnhausen's book the "Smith&Wesson revolver a shop manual" Midway sells it the cheapest about $25 and well worth it.

And read it then decide if you want to do the repair yourself, you can probably send it to S&W for repair as well, if it was made after 1988 it will be free.

What is the model and age of your revolver??

 

[Markbo]

I like working on my own guns. I have seen my gunsmith do this type of work. Because of the accuracy needed in this area, unless you have some very high quality machine tools, I would recommend this as a gunsmith only repair.

In fact, if it is not within spec, I would contact S&W and have them fix it. They will probably do it for free. Free is good!

 

[unspellable]

End shake in the S&W

Go the shim route. Easy to do, easy to undo, unlike yoke stretching, it can be done multiple times, and it's cheap. And for my money, the results are better than stretching the yoke.

If the end shake is due to wear, you should dress up the yoke tai land cylinder well bottom before adding shims. Most end shake cases I've seen were due t opoor fitting at the factory rather than wear, in which case the shims are a drop in deal.

 

[Confederate]

Well, since the gun is a Rossi, I doubt whether Smith would be interested. I like to do things myself, but getting the right shim is the problem.

This was my approach:



Trying to get a shim to these specs is my primary problem.

Am I right that rubber washers would melt away from the forcing cone gas and flame emissions, or is it far enough away to survive? Thanks for the responses. If anyone can tell me what tools I'd need to stretch the yoke and square it off, I could order them from Brownells. The book on S&W revolvers from Midway also looks good.

 

[dfariswheel]

The problem with your Rossi is we just don't know what system they used to position the cylinder on the crane.

S&W, is positioned by the end of the yoke (crane) barrel touching the rear of the cylinder in the cylinder axis hole.

Colt is positioned by the collar on the front of the cylinder contacting the frame on newer models, and by contacting the flange on the crane on older models.

Trouble is, WHICH did Rossi use, or did they use something entirely different.
While your gun LOOKS like a older Colt system it may really be a S&W system.
Installing a washer on the wrong system will wreck the gun.

Before you start sticking washers in or stretching the crane barrel you better find out what you've got. Get it wrong, and you'll destroy the gun.

Also, rubber or synthetic washers won't do it. They'll burn up, AND they'll compress and flex, making the cylinder assembly batter itself to death in short order.

 

[Confederate]

The Rossi is a S&W clone. As such, they stole the whole design. I've had the plate off and it's pretty much a carbon copy, and a surprisingly good one when one considers that people actually bought Llamas!

The washer I improvised seems to work just fine, but the B/C gap is a little more than I'd like. In the past, every time I've had someone fix an endshake problem, they either moved the cylinder too far towards the forcing cone, making the headspace off the back excessive, or they've moved it back, opening up the B/C gap. That's why endshake can be a tough problem to solve.

I don't know which part of the yoke would have to be stretched, but if doing it would solve both problems, yes, I'd be willing to pay to fix it.

MM Gunsmithing took over the repair of the old Rossis, so I'll most likely take it there. The gun came from the factory with the endshake, so it's something I should have caught early on, but didn't.

It's a nice little piece. It's really grown on me.

 

[Markbo]

So if I understand correctly, to 'fix' the excessive endshake you are doing this by increasing the barrel/cylinder gap by using shims to push the cylinder further back against the frame. Is that about right?

 

[Confederate]

That's correct. As long as I can get a B/C gap of .008 or so, I can live with it. I can't live with misfires. So if I have to push the cylinder one way or the other, I'll push this one back a little so it won't jump forward when the firing pin strikes the rim of the cartridge. I think that's where I'm getting my misfires.

I'd much rather have a gap of .004, but in this case it doesn't seem possible.

 

[dfariswheel]

When correcting end shake, you ALWAYS move the cylinder to the rear.

Moving it forward increases the head space.

As for the above Rossi, I still don't know WHAT positions the cylinder.
Is it the flange on the crane, or is it the shaft of the crane contacting the bottom of the hole in the cylinder.

If the cylinder is positioned by the flange, you CAN'T stretch the crane shaft.

 

[Confederate]

It's the shaft of the crane contacting the area at the bottome of the hole in the cylinder. When one pushes the crane into the hole of the cylinder/extractor, it contacts the area near the extractor star. It leaves just enough space for the cylinder to ride forward just enough to where it could rob the hammer from a solid strike. The B/C gap decreases at that moment, but the discharge pushes the cylinder back towards the cylinder shield. By putting in the washer, I keep the cylinder from coming forward when the hammer is dropped.

If I could reduce the B/C gap and solidify the cylinder, I'd be very happy, but I may have to live with the gap if I understand the nature of the repair.

 

[JERRY]

i had S&W fix my model 60 NY-1 at the factory for end shake....didnt cost me a penny and turn around time was about two weeks.

 

[Markbo]

dfaris - That was kind of my point. If you 'fix' endshake in the manner you are proposing, you are creating another problem, i.e. excessive cylinder gap. This could in turn result in more problems.

Therefore I go back to what I said originallly. Let a gunsmith do it. They will weld up the cylinder to ensure that it is fit correctly and not shimmed - which to me on a handgun is a very Duct Tape kind of patch.

 

[Confederate]

Thanks. I think you're right.