End shake questions

[m75rlg]

I have a simple cylinder end shake question.

I have two 29-3s. One in which the cylinder endshake goes from a max of .007" when the cylinder is held toward the recoil shield, and will pinch a .0015" guage when pushed toward the forcing cone. Without the guage, it appears the cylinder will contact the lower edge of the forcing cone.

The other has a max of .011 forcing cone / cylinder gap to nearly making contact with the forcing cone, pinching the .0015 guage.

I've tightened the yoke retaining screw on the first one, which was lose, and solved the yoke end shake that was present before making the measurements above.

I've never done this, but have read the info on the board about endshake and looked at the Midway video of installing end shake bearings.

My questions are, if I understand it correctly, the end shake bearing will move the cylinder back toward the recoil shield. Is that correct?

If that is correct, should I buy .002 bearings and install 2 or 3, or would I be better off to buy .004 bearings and just use one? I don't want the forcing cone to cylinder gap to get out of specs, and in your opinion would this approach improve the revolvers?

Thanks in advance.

 

[OKFC05]

Well, I'd square off the end with the cutter tool, so the actual amount you need is unknown until you get into it. So a tool, plus a packet of each shim thickness to do it right.

Or let someone with the proper tools and experience do it for you.

 

[jaybar]

"..... the cylinder endshake goes from a max of .007" when the cylinder is held toward the recoil shield, and will pinch a .0015" guage when pushed toward the forcing cone. Without the guage, it appears the cylinder will contact the lower edge of the forcing cone. "

A little vocabulary lesson first: endshake is the total movement of the cylinder. Cylinder gap is that space between the cylinder and the barrel that you measure with a feeler gauge. You calculate endshake by subtracting the difference between the cylinder gaps when the cylinder is held all the way back and when it is pushed all the way forward. Sounds like the endshake in the description above is .007.

You shouldn't try to get the endshake down to zero. If you do you'll likely get a binding of the cylinder where the ratchet is being forcibly pressed against the recoil shield. You should leave about .001"-.002" endshake in to allow for free rotation of the cylinder. Having said that, you will probably need to use more than 1 washer to take up the endshake ( 1- .004" plus 1 -.002" or 3 - .002"). I've not seen any difference in operation when using one .004" or 2 .002"

 

[texagun]

I fixed the endshake in a Model 686 with endshake bearings purchased from Brownell's. The 1st time I tried it, I used 2 bearings and they bound up and I had to remove them. Then I just used one bearing and it has worked fine for the last 2 years. I would recommend using only one bearing in lieu of using 2 or 3 together.

 

[haggis]

The second gun may have a B/C gap problem when you fix the endshake. You'll have about 0.010" B/C with 0.001" endshake. That's getting to be a bit much, although it should still be functional, as long as the bore and chambers line up. Just watch for spitting from the B/C gap.

If you need to use multiple shims, be sure to lubricate them well (Break-Free works well).

Buck

 

[m75rlg]

Thanks for the info and advice. ("Cylinder gap" - got that.)

Right now, running this over in my mind, it sounds like a plan might be to use one .004 bearing in the first revolver, and two .004 in the second. That would leave .003 endshake in each revolver. Would that sound accecptable?

You know, the funny thing is the revolver with .011 endshake suprised me because I thought it felt tighter than the 1st one. Neither has shown any tendency to spit or shave lead. I shoot mostly jacketed soft points in a hunting load over H110.

OKFC05, what are you talking about "cutting"? Are you speaking of trueing up the yoke or the forcing cone?

 

[stevieboy]

This is probably a dumb question but is a small amount of endshake something that needs to be corrected if there's no lead shaving and the gun is accurate? Only one of my Smith revolvers locks up completely tightly. The others all show a small amount of fore-aft play, some more than others, with lockup. I've never worried about it because they're all extremely accurate and show no signs of lead shaving. Am I wrong about that?

 

[haggis]

No dumb questions if you need to know something. Factory specs on endshake are 0.001" (+0.001", -0.000") - maximum of .002". As endshake grows, the end of the cylinder yoke takes an increased pounding during firing, the yoke end wears, and endshake increases further. Heavy loads exacerbate this, as do a large number of normal loads.

I've seen many guns with 0.003"-0.004" endshake that work perfectly. I probably wouldn't worry about it until it gets to this level. For S&W revolvers it's such an easy fix that there's no reason to let it get past this point. Endshake on Colts is much more difficult to fix without some rather specialized tools.


Buck

 

[Carl Williams]

M75RLG,
I have been reading this thread with a great deal of interest:

1. I also have an S&W M29 (dash2) w/8 and 3/8" barrel along with two other N=frames (M57 (dash nothing) and a 25-5. I have reloaded ammo for 40 years..
2. I believe we live close together (I live just south of the Asheboro, NC. zoo, in "Pottery country").
3. I am also a Veteran (Air Force in the mid sixties, 3 yrs in Germany).
This is where I whetted my appetite for firearms (M-61 Vulcan 20mm rotary cannon on the F-105D and F. I was a Offensive Weapons Control Systems technician/36th TAC Fighter wing, Bitburg Germany).

If interested, we might meet and compare notes on our N frames, spec's, etc. I have a few precision measuring tools, also. I am retired, so I have time, but no money, no job, no stress and no sex! Just let me know.

Best Regards,
Carl

 

[OKFC05]

Thanks for the info and advice. ("Cylinder gap" - got that.)

OKFC05, what are you talking about "cutting"? Are you speaking of trueing up the yoke or the forcing cone?

YOKE FACING REAMER
MfrOWER CUSTOM
Price:$46.92

Squares Rear Face Of Yoke Barrel
Eliminating manufacturing variations is the secret to a good revolver tune-up. Toward this end, the Ron Power Yoke Reamer lets you make sure that the rear bearing area of the yoke is absolutely square to the yoke barrel. Once everything's square, it's easy to eliminate cylinder endshake using the Power Cylinder Endshake Bearings. Reamer pilot fits the yoke I.D. on S&W K, L and N frames, Ruger Speed and Security Six.

BROWNELLS : POWER CUSTOM : YOKE FACING REAMER - World's Largest Supplier of Firearm Accessories, Gun Parts and Gunsmithing Tools

 

[m75rlg]

Thanks, OKFC05.


Carl,
Did you get the PM I sent?