Cylinder radial play, s&w14

[Ugluk]

I'm in the process of checking over my trusty old m14-2 since I haven't managed to get those itty bitty groups from a ransom. Best so far is 1 1/2" at 28yards.

I can feel a play in the front cylinder bearing. I can think of no way of measuring the actual play, but I'm estimating 1/100" or quite close. Is this excessive?

The yoke o.d. measures at 0.3839" and is fairly round.

Is there service limit measurements available for various parts?

One reason I worry about cylinder alignment is that all my recovered boolits are heavily damaged down one side with the rest showing clear engraving. There also is leading in the lowest part of the forcing cone.

I'd really hate to have to send the gun off to a smith somewhere, as it'd be really expensive and I would be without a gun for way too long.

Any help would be greatly appreciated. I've searched the forum a lot, but come up with nothing on radial play.

[stubshaft]

When you say that you feel play do you mean radially? (when rotating the cylinder) or when you move it foreward (toward the muzzle) or backward (toward the recoil shield)? Based on your recovered boolits my best guess is that the cylinder is not locking up properly. You would need to get a "range rod" to check this. The only cure is to send it to a gnsmith who is familiar with "timing" a S&W and have a new locking bolt fitted.

[machinisttx]

The yoke has bearing surfaces, but there are no bearings for rotation. How are timing and endshake? Lockup reasonably tight? Are you certain that the yoke hasn't gotten warped?

Bad timing, loose lockup, or a warped yoke could cause what you are describing. The use of a range rod(check brownells) mentioned by stubshaft will tell you how well the cylinder is aligned with the bore. You'll need a different tool to check the yoke alignment.

A new cylinder stop will require fitting and will correct loose lockup. The hand will have to be replaced(fitted part as well) to correct any timing issues. If the timing is correct and the cylinder isn't aligned with the bore, the only cure is a new cylinder, which is a factory or factory certified S&W service center only part. If gauging the yoke shows that it's out of alignment, you'll have to use a wood or nylon wedge and/or a hammer to realign it.

I suggest purchasing a copy of "The S&W Shop Manual" from brownells or a similar source. If you're not very patient or mechanically inclined, it's a good idea to let a 'smith work on it.

[cajun shooter]

As a S&W trained armour I will say that a lot of what needs to be checked requires special tools and knowledge to use them. Be very careful if you decide to do it yourself. Endshake can be solved a few different ways. Timing of the hand and cylinder stop requires a step above kitchen table gunsmithing. If not sure send it out.

[Ugluk]

When you say that you feel play do you mean radially? (when rotating the cylinder) or when you move it foreward (toward the muzzle) or backward (toward the recoil shield)? Based on your recovered boolits my best guess is that the cylinder is not locking up properly. You would need to get a "range rod" to check this. The only cure is to send it to a gnsmith who is familiar with "timing" a S&W and have a new locking bolt fitted.

Yes, I mean radially as I can wiggle the front end of the cylinder side-to-side or up-down by approximately 1/100".

Now that you mention the locking bolt, I realize I didn't have the cylinder closed when wiggling it. I have to go back and see if it tightens up any with the locking bolt engaged. I was under the assumption that the cylinder rotated on the surfaces of the yoke, but now I'm realizing that the center pin is the actual axle, and aligns by the locking bolt and the hole in the recoil shield.. D*mn! I feel stupid..

Endshake is good, as is forcing cone-cylinder clearance.

My right ear tells me the cylinder locks up just a tiny fraction before hammerfall in DA in all six chambers. Two of them possibly later than the others by a hair.
A light shining at the recoil shield indicate no visible misalignment when looking through the barrel, but lockup is a bit sloppy with some movement.

Could it be overtravel of the cylinder? Shouldn't the most of the leading be to either side of the forcing cone if that was the case?

The range rod, is its intended use to be inserted in the barrel and indicate misalignment by snagging on the edge of the chambers? If so, I think I can whip up something equivalent without having to wait for shipping.

Machinisttx,
I don't know yet how the yoke is aligned, will investigate.
I am very patient and not at all hamfisted, but I'm still learning this. I love to fix and improve things and can go to great lenghts to learn something I could have had somenone else do for me in 5 minutes. I don't yet know if it is a character flaw or a virtue. I will certainly get the book.

Thank you both for your kind help.

[HeavyMetal]

I will second Cajun Shooter suggestion on he S&W manual as well as suggest Kunhuasens book on the smith as well.

I've never seen the S&W manual, in person, CS speaks of but I do have several of the Kunhuasen manuals and they are very complete and discuss both end shake and timing to a great degree

[Ugluk]

CajunShooter,
You replied while I was agonizing over my post and studying parts diagrams. Thank you for taking the time advising me, I'm at this stage only trying to make my own diagnosis and learn the finer workings of my revolver. I will certainly not try advanced gunsmithing unless I know 100% what I'm doing, and have a backup plan in the event of unforeseen mishaps.

Heavymetal, thank you for directing me towards the Kunhausen book. Will check it out.

[machinisttx]

CajunShooter,
You replied while I was agonizing over my post and studying parts diagrams. Thank you for taking the time advising me, I'm at this stage only trying to make my own diagnosis and learn the finer workings of my revolver. I will certainly not try advanced gunsmithing unless I know 100% what I'm doing, and have a backup plan in the event of unforeseen mishaps.

Heavymetal, thank you for directing me towards the Kunhausen book. Will check it out.

Kunhausen is the author of the S&W shop manual and many others. It's a good thing to have if you want to know more or want to know what to look for when you have a problem(and how to fix it).

[Ugluk]

Would this be the book recommended?
http://www.brownells.com/.aspx/pid=25717/Product/THE_S_W_REVOLVER___A_SHOP_MANUAL

I just got home from work, and though I really should get something to eat and head for bed I couldn't help myself but bring out the m14 and a set of calipers. Some careful measuring between top strap and the closest cylinder stop groove show a rotational play of 0.0177".

The cylinder also can also be wiggled side-to-side when in the frame, but less so up-down. Holding the locking bolt fixed makes some but not much difference, so am I wrong in guessing yoke to cylinder fit might still be an issue?

[44man]

Talking about S&W yokes, long, long ago before I had tools, a neighbor brought over a S&W .38. The cylinder would not close because he bent the yoke doing the movie thing of twisting his wrist to open or close the cylinder.
I kept thinking of a tool to make but just for the heck of it I grabbed the cylinder and gave it a twist by hand.
Straightened the booger right out and everything was in perfect alignment.
Got me to thinking real hard about how soft it was. :sad:

[fecmech]

I would send it back to S&W and have them repair it. Nobody will do it better or more inexpensively.

[Ugluk]

I would send it back to S&W and have them repair it. Nobody will do it better or more inexpensively.

If I lived in the US I would consider doing that. Here in Sweden, customer service is non-existent. The S&W importer have even stated that they will not even import and certainly not stock small spares, barrrels or cylinders. They just sell the guns, lighters, money clips and other pointless items. Really disappointing.

There are a few reputable revolversmiths here in Sweden, and they're swamped with work and charge accordingly. If it comes to replacing any important part it'd probably cost me more than the revolver. The shipping alone would set me back $150..

44man,
I've read of the yoke being soft, as the rubber kind of speedloaders could bend the yoke when it was torn free of the cartridges.


So, nobody knows what dimensions a yoke start out at, or if my slop should be considered excessive? or is it unimportant?

Perhaps this is a well kept secret within the gunsmithing community..

[leftiye]

It is excessive. Minimum clearance that turns, and will stand a little dirt is good. Call Brownells (or get one of us to if the phone call would bankrupt a wealthy man), their techs are gunsmihs, and are free with knowledge (only gunsmiths I've met who don't think everybody else is an idiot). Or, get some of us to mike their cranes and find out what size they are.