Jammed my S&W Model 60 today

[IrvJr]

Hi Folks,

I took my Smith & Wesson Model 60-14 (.357/.38) to the range today. I shot 50 rounds pretty quickly through it. Not quite Jerry Miculek speed, but I would shoot five rounds pretty quickly, unload the cylinder, reload, then fire again. During the last few of cylinders I had trouble working the trigger. If I pulled it in Double action mode, I felt resistance.

I looked at the gun and did some checks. If I opened the cylinder, but moved the cylinder latch back with my thumb (to simulate the cylinder be closed), the action worked very smoothly. If I closed the cylinder, the action would sometimes bind (even when the gun was empty). The guy shooting next to me (who was also shooting some S&W Revolvers) looked at it as well and he thought it could be the gun was very dirty (I thought so too - I just shot 50 rounds of lead bullets through it... Federal .38sp LRN).

Anyway, I put the gun away and when I got home I inspected it. It seemed to work fine. If I looked at the face of the cylinder I could see metal scratches like it was rubbing against the barrel/forcing cone. I think what happened was the little barrel got hot and expanded, and the carbon and lead build up also built up the area in between the cylinder and the barrel.

The gun worked great when I got home. nothing was binding anymore. I cleaned it anyway and soaked the barrel, chambers, breech face, and cylinder surfaces with Hoppes #9 then wiped everything away.

Do you think it was the heat that caused the failure or just a build up of crud. I tend to think it was the heat because it was binding at the range, but when I got home it worked fine (I assume because the gun had a chance to cool off).

Any ideas on what the problem was?

Thanks in advance!

[Sevens]

My first guess is always going to be the same: ensure the ejector rod was not unscrewing and coming loose. These days, it has a REVERSE THREAD so to tighten it is the opposite direction, that would be counter-clockwise to tighten.

If the ejector unscrews even a wee little bit -- the whole revolver binds anywhere from "this doesn't feel right" to "OH MY GOD, I KILLED IT!"

Check that, double check it.

[IrvJr]

Thanks for the tip Sevens. I checked the ejector rod and it's still tight. The more that I think about it... I guessing it was mostly due to the build up of carbon and lead around the forcing cone and maybe the barrel expanded because of heat (or not). The gap between the cylinder face and the barrel/forcing cone is pretty small (just looking at it by eye... I didn't try and measure it with gages or anything, but it's pretty tight when compared to my other revolvers) and I think shooting the lead round nose bullets combined with carbon from previous range sessions built up the crud around that area and was probably interfering with the cylinder.

I'll be careful to clean it more carefully and start reloading again (I use Rainier copper coated bullets for my handloads).

[gus3836]

Sometimes if you get wee bit of dirt under the ejector star that will do it also.
It does not take much to do it.

[Sevens]

^Oh, heck, that is a -big- one also, I can't believe I forgot that.

It may sound hard to believe until you experience it -- in fact, you can replicate it at home. Carefully. Try placing some schmutz under your ejector and feel, right away, how quickly the revolver gets VERY unhappy.

I really would say that is more likely then stuff at the front end, at the flash gap.

You could go ahead and measure the flash gap you know, all you need are feeler gauges. Next time you are at an auto parts store, you may be surprised at how little it costs. You are looking for around 6-thousanths of a gap, more or less.

[IrvJr]

Thanks for the tips. It might have been dirt under the star too. Now I know what to look for. I might invest in some feeler gages too.

Thanks again!

[gyvel]

Do you think it was the heat that caused the failure...?

That's an old story that can affect some guns where you have components made of two different alloys that expand at uneven rates, causing binding.

When the Ruger Redhawk stainless came out we sent several back to the factory for that very reason. A combination of close tolerances, plus uneven heat expansion caused the guns to bind up. When brought in for "repair" after cooling off, they worked just fine. Check your cylinder gap to see if it is exceptionally tight

The comment about schmutz under the extractor star is also another common cause of the binding/dragging you describe. Try giving the gun a good cleaning and let us know how it works out.

[Sevens]

I can tell you that I have had -two- Dan Wesson 15's and heat expansion absolutely binds them up a little bit in double action, extremely easy for me to feel and it is not because I set the barrel/cylinder gap too short.

It was a thought I figured I might be experiencing...
So I've tested it. Start with a clean revolver, shoot a bunch of ammo at a rapid pace and even wipe down EVERYTHING with a clean cloth, and still feel it binding.

Sit it down on the table for a half hour, pick it up and feel it move smoothly with no binding whatsoever... On my Dan Wesson revolvers, it simply must be heat expansion. Nothing else reasonably explains it.

[James K]

You might check the barrel-cylinder gap with a feeler gauge or a piece of printer paper (usually .003" thick); if it is under about .003", you could have binding due to heat buildup. Over that, crud is probably the explanation.

Jim

[pete2]

The most likely problem is a little crud under the extractor. I was shooting IDPA with a 586 loaded with Green Dot and all it took to bind was a flake or 2 of unburned powder. The other thing is the rod. it can back out and lock up also.

[IrvJr]

Hi Folks

I'm pretty sure it's the cylinder gap. I used a fresh sheet of paper and tried to measure the gap. It's about the thickness of the paper.

It's pretty tight but I don't know if I'll have it serviced. I can shoot 50 rounds through it at a pretty brisk pace before it started to bind and the gun is very accurate for a 2" barrel so I think I might keep it as is and use other guns for high volume fire.

[Pond, James Pond]

I can shoot 50 rounds through it at a pretty brisk pace before it started to bind and the gun is very accurate for a 2" barrel so I think I might keep it as is and use other guns for high volume fire.

That's probably about 38rds more than it was designed to shoot briskly, in succession!!

[Super Sneaky Steve]

If you're getting lead build up you may have a timing issue.

[Webleymkv]

If your B/C gap is too tight, you should probably check your revolver for endshake (fore/aft movement of the cylinder when closed). To check it properly, you really need a set of feeler gauges. Grant Cunningham has an excellent article about it on his site:

http://www.grantcunningham.com/2007/...e-of-endshake/

As you can see, if endshake is excessive it really needs to be corrected as it allows a "jackhammer" effect on the cylinder when the gun is fired which will progressively make it worse. On a S&W revolver, there are two ways to correct excessive endshake: stretch the yoke with a special tool (this is how the factory does it) or install endshake bearings (much easier to do yourself and reversible). Fortunately, endshake bearings are very inexpensive and, so long as you're comfortable removing the ejector rod assembly from the cylinder, easy to install.

http://www.brownells.com/rifle-parts...-prod9858.aspx

[James K]

I am not sure I see the connection between a tight b/c gap and excess endshake; they are almost opposites. If the headspace is correct, a tight b/c gap won't allow end shake. Also, if the cylinder can move back and forth, it won't bind due to a tight b/c gap, since the gap will vary as the cylinder moves and usually you end up with an excess gap, not a tight one.

In an S&W, end shake is usually corrected by shimming the cylinder arbor, which forces the cylinder away from the barrel, not up against it.

Jim

[Webleymkv]

Originally posted by James K
I am not sure I see the connection between a tight b/c gap and excess endshake; they are almost opposites. If the headspace is correct, a tight b/c gap won't allow end shake. Also, if the cylinder can move back and forth, it won't bind due to a tight b/c gap, since the gap will vary as the cylinder moves and usually you end up with an excess gap, not a tight one.

Excessive endshake allows the cylinder to slam back and forth under recoil. As the cylinder "jackhammers" to and fro it will peen the end of the yoke which fits up inside the cylinder. As the Yoke is peened, it will allow the cylinder to creep closer and closer to the forcing cone. Also, when the cylinder is closed, the bolt plunger spring is pushing forward, albeit lightly, against the center pin. Because the center pin spring is quite stiff, the entire cylinder assembly will be pushed forward as far as the yoke will allow it to up to and including contact with the forcing cone.

You will only see excessive b/c gap with endshake after the endshake itself has been corrected by either shimming or stretching the yoke. Also, excessive b/c gap usually only occurs if the enshake was caused by frame stretching.

In an S&W, end shake is usually corrected by shimming the cylinder arbor, which forces the cylinder away from the barrel, not up against it.

Exactly right, but if the OP's revolver has excessive endshake which has not been corrected, the bolt plunger spring may be pushing the cylinder assembly up against the forcing cone. So long as the endshake isn't too bad, simply shimming the yoke would solve the problem.

[jglsprings]

Mine let me down at the range last Sunday - the trigger reset "hung" - jammed - sluggish.

Very repeatable. So it went to "my guy" that does my smithing. He is going to look at it and also smooth the action up.

Can't complain - it's been in service for 10 years and shot every other week (on average).

I was surprised when it hung up. All the revolver guys that talk about "never fail" should have been there.

[kcub]

You could have carbon buildup in one cylinder causing the case to stick back and making it sluggish when it "revolves".

[4V50 Gary]

Not allowing the trigger to reset?

[James K]

Webleymkv wrote:

"As the cylinder "jackhammers" to and fro it will peen the end of the yoke which fits up inside the cylinder. As the Yoke is peened, it will allow the cylinder to creep closer and closer to the forcing cone. Also, when the cylinder is closed, the bolt plunger spring is pushing forward, albeit lightly, against the center pin."

When the revolver fires, the case grips the chamber walls and the cylinder recoils backward, away from the arbor and away from the forcing cone. The ratchet bangs against the recoil shield and eventually the ratchet and/or the frame will wear enough to cause end shake. Shimming the arbor is done to compensate for that wear*, not for wear on the arbor itself. Shimming forces the cylinder back as far as it will go, increasing the b-c gap, though usually not enough to cause serious problems in that area.

When the cylinder is closed, the center pin spring fits through the hole in the frame and forces the bolt back, allowing the hammer to move; at that point, the center pin is at its full rearward position and it is exerting no force on the cylinder to move it forward. The bolt spring is so light that its effect on the center pin and cylinder is neglligible.

*And for frame stretching, a less common problem unless the gun has been fired extensively with "hot" loads.

Jim