Have here a recently acquired 36-1. This revo appears to have been fired very little, if at all.

Trigger rebound is very lazy/sticky. This is with the heaviest rebound new spring installed.

I have deburred everything following Jerry Miculek's DVD (done this many times). Rebound is still bad.

After examining everything carefully for obstruction it appears as if the outside of the hand is dragging in the window like the hand is a bit too thick (or window too narrow). Checked the inside window edges for burrs - they're clean.

Only think I can think of is to stone the hand for additional clearance.

Any other suggestions?

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-jwk-
US Army '72-'95

I would stone the right side of the hand itself, avoiding the face that contacts the ratchet.

Thanks for the sanity check. Exactly what I was contemplating doing..

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-jwk-
US Army '72-'95

I'd advise against stoning the hand. The normal way to correct this is to file the inside face of the window. BTW, Brownells sells window files specifically for doing this.

I disagree. I think the more easily replaceable item should be worked first. Unless there is a burr or something in the window. But, then you could wait for Microsoft to come out with a new version.

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NRA Benefactor

If you were to widen the hand window, you would remove material from the left side of the window - correct?

(I think "left" is what scooter meant by "inside" face.)

The left side of the gun is the one with the cylinder release button. He stated that the window had no burrs so, I am assuming it is OK. The hand is probably just a tad too thick. Slightly breaking the sharp front edge of it on the right side may be all it needs. To be certain, you could remove the hand to see if the trigger rebound improves.

Yes, gun runs fine with the hand out of there. That's how I finally deduced it was the problem..

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-jwk-
US Army '72-'95

Scooter123 is absolutely correct. Hand window files are intended to be used to widen the hand window to fit the frame to the hand. When fitting an oversize hand this is nearly always necessary.

Read the sig line if you have any questions.

TinMan, yes, the window needs to be filed on the inside face, toward the center of the frame

Thinking I may just pack this one off to Springfield. This is getting way beyond the "fluff and buff" I'm comfortable with, and equipped to do.

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-jwk-
US Army '72-'95

Can you please explain how filing on the window toward the center of the frame will correct this if the right side of the hand is rubbing the frame window closest to the outside of the frame? Im sure there is an explanation but, Its not computing in my brain. Also, why is it a bad idea to remove a couple of thousanths from the surface of the hand? Just curious. Thanks

If you file the window you file the lh side. Thats the side by the cylinder release.

You never file the hand. First the hand is hardened and the file won't cut it. Second, the hand thickness is what turns the cylinder to the proper carry up.

I posted this in the past. Copy and pasted for your pleasure.


Hand fitting does violate "file the cheapest part" rule. Before a wider hand will do any good, it must catch the ratchets closer to the center of the cylinder. This means you must file the hand's window only on the left side and only enough to allow the hand to move freely in the window. If you take metal off of the right side of the window or from the hand itself, you won't accomplish a thing, in fact you might make timing worse. In other words, you have to move the hand's point of contact to the left.

Installing a wide hand compensates for wear on the ratchets outer edge. The idea is to force the cylinder to turn a little farther and get a good lock-up. If the left tip of the hand is worn, it will not rotate the cylinder far enough. In this case, you can install a standard width hand to restore timing.
Hands are made of some hard stuff. It is a good idea to use some 400 grit sandpaper to break the sharp front edges of the hand so it won't bite into the window.

DCU or timing
DCU (doesn't carry up) or basic timing is easy to check.
How I check basic timing is pretty easy to do. Without touching the cylinder or holding back the cylinder just gently cock the hammer slowly in single action, (on all stations) and see if the cylinder stop snaps in place before the hammer falls. When the trigger is pulled to the rear (MIM triggers will rotate the cylinder further when the trigger is pulled) the cylinder stop must snap into the cylinder notch, if not, then you have a problem.

One thing I must insist, before swapping the parts make sure it's not a loose fitting ejector causing your dry fire and poor carry up problems. This is true with non-pinned cylinders. Drop empty cases into the chambers then check your carry up. Sometimes the gun is fixed when cases are inserted in the chambers.
As the extractor ratchets, hand, and hand window wear, they get to a point where the hand won't rotate the cylinder far enough to allow the cylinder stop to snap in before the hammer drops (carry up condition in DA mode). This is not a hand length issue, it’s a hand width problem. If you take the side plate off and watch carefully in the hand window while pulling the trigger, you will see the hand cams off of the ratchets and the left side of the hand tip positions against the right section of the ratchets to rotate the cylinder those last few degrees.
Unless a gun has been fired a zillion times, the hand and the window seldom show wear, except for the left tip of the hand. Most times when you see a hand loose in the window, it's because it was shipped that way.

Factory hands run from about .093 to .095" and wide hands run about .098 to .100" There shouldn’t be more than .001 side play between the hand and window.
If the hand has worn thinner, or the hand window has worn wider, or the edges of the ratchets have worn thinner, you will start loosing carry up. Without fail, the ratchets are the most usual cause.
There are several solutions. The absolute best one is to replace the extractor (ratchets). Unfortunately, that’s a factory fitted part and you can't buy one without sending the gun back to the factory.

The next best option is to fit a wider hand. This will have nearly the same effect as a new extractor because it will take up the slack from ratchet wear and make the cylinder rotate a few more degrees. When the wider hand is fitted, you must widen the left edge of the hand window so the hand will be positioned a few thousands to the left.

An undesirable option is to lay a fine bead of weld on the right edge of the hand window then dress some material from the left edge of the window. This will position the hand closer to the ratchet and make the cylinder rotate further. Welding that thin of metal is sure to do some damage to the finish and could ruin the frame.

You can bend the tip of the hand slightly to the left. This will also cause the cylinder to rotate a bit father. The hand is made of some very hard material and will fracture if you try to bend it without first softening it. You have to heat the tip of the hand until it is red hot then let it cool to room temperature. It will then be soft enough to bend without breaking. Once you get the hand tip bent, you must re-harden the hand. Herein lies the problem. Most of us don't have the proper metallurgy skills to re-harden the hand. If it is soft, it will soon wear out.
One of the very precision specs in an S&W revolver is the hand-to-ratchet clearance. A few thousandths makes the difference between good and bad carry up. You want the hand tip to be touching the ratchet but not binding on it when the trigger is pulled. Basically a zero clearance.

If you insert the tip of the hand into the window, it should move freely with minimal side play. The tighter the better, as long as it doesn't bind.
The left side of the window creates a reference point in respect to the ratchets. You must move the reference point to the left before the wide hand will make the cylinder rotate more. That means you must take metal off of the left side of the window. Use a "safe" window file for this. Taking metal off the hand or the right side of the window moves the reference point the wrong way.

Once your wide hand is installed, the tip of the hand may bind on some of the ratchets. This will cause a bad gag in DA trigger pull. With the side plate off, watch through the hand window as you cycle the gun in DA. You will see where the hand cams off of the ratchet and the point of contact between the hand tip and each ratchet. Dress the ratchets at the point of contact so the hand is touching but not binding.

Go slowly changing the hand. It's easy to do and will fix your timing (DCU) problems.

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NRA Benefactor Member

I think you mean LH side?

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NRA Benefactor Member

Well that explains a lot. Thanks

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NRA Benefactor

I had an action job done on a 642 because it felt like it had a "snag" in it, toward the end of the trigger pull. After the action (and springs) were re-worked by the master gunsmith it still felt like it had a snag in it. I took it back to the gunsmith and had him fire it at the range...he then found out that THIS (hand in the window issue) was the problem I was feeling. Not sure what he did to remove the interference (or burr?), but it is wonderful now. Never knew this could be a problem, and you're the only other person I've heard discuss it...best wishes, B

First- determine that the hand is seated fully on the trigger.
Second- with a Q-Tip lub the internal parts.
Third- Determine that the trigger return spring housing is smooth along with the frame area that it travels on.

Always check the simple corrections before reaching for the file.

Thanks, everybody, for your input.
Obvious this is outside my power curve.
If I can't find a real revolver smith locally, its off to S&W.

Case closed.

-jwk-

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-jwk-
US Army '72-'95

I fully respect JWK's decision to have someone else fix his revolver. However, I learned a lot from reading this thread. Thanks guys!

It is often best to describe which side of the revovler to work on, e.g. the hand window, as the sideplate side or the frame side. We did this at the factory and then there was no confusion of a left or right side.

Hope this helps
chris

Exactly. Same with vehicles. In the Army, I learned to use "curbside" and "roadside". Works well, as long as we were in places where they drive on the right.

That's why I made an image of the problem.

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-jwk-
US Army '72-'95

Before you do anything I'd look to see if the hand pins stick out the left side of the trigger. That can cause a bind. Trim as required.

Does the hand BY ITSELF bind in the window? If it does there's a problem. If it slides thru the window freely that's NOT the problem.

The hand pins could be out of square to the hand and causing a bind. That will load the hand against one side of the window.

If the hand is "too thick" it will bind in the window, not just against one side.

Have you measured the Hand? Could you have a large hand, and the problem could be resolved by installing the narrower hand and no filing would need be done?

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H Richard
SWCA1967 SWHF244