Sideplate Issue

[PRM1]

Cleaned my (new to me) Model 64-4 last night. If I tighten the back two screws on the sideplate all the way down the action binds. Turning them back less than 1/4 turn and it works perfect??? The guns is pretty much mint. I've never had a S&W do this. Should I go with it and not worry or should I take it to a gunsmith/or back to S&W for repair. Not really concerned about them backing out. The back screw is covered by the grip and the other is somewhat snug.

Screws are in the right holes.

 

[Tom S.]

If the screws cause the action to bind, there is something wrong!

 

[AveragEd]

Sounds like the transfer bar might be improperly located. If the hammer was not seated fully, the plate couldn't be tightened to flush with the frame.

Ed

 

[JohnK]

The transfer bar needs to be UP, before reinstalling the side plate.

It will bind, or worse, if you don't do that.

 

[PRM1]

JohnK, I assume you mean the hammer block being in the up position. This was installed correctly. I am at a loss over what is binding. Its only a minute fraction of a turn between binding and working like it should with it backed off??? I am definitely at a loss.

 

[growr]

Are all of the screws in the right holes? They ARE fitted.....

Randy

 

[mc123]

CAUTION: I'M NOT A GUNSMITH. ALL ADVICE TAKE AT YOUR OWN RISK!

If you're not sure in any way, I'd send it to S&W or a competent gunsmith.

Now that's out of the way and you still want to work on it, this is my understanding: All the screws do is hold the plate in place. The yoke screw also holds the crane/cylinder in place. You should be able to tighten them snugly all the way with no binding.

After reassembling your k-frame, the last screw on the frame I tighten is the strain screw that holds mainspring. When you didn't mention this, you may be out of sequence in reassembling. A fully tightened strain screw means the mainspring puts full force on the hammer assembly which rotates on the frame and the sideplate.

Of course you have to remove grip to do this. From the limited information given, I'd do the following:

1. Remove grip. Loosen the strain screw, but not so much that the mainspring completely pops out.

2. Remove all three screws. Carefully, without banging the cylinder against the frame, remove the crane/cylinder assembly.

3. Use the tapping method across the grip location with a wood hammer handle. If this is not familiar you're going have to research this. It's the only recommended method I know of to properly remove the sideplate.

4. After the plate is removed I'd check:

a. Make sure all components are firmly (but gently) press down.
b. Recheck the hammer block location. The slot of the hammer block should be on the pin that's part of the rebound spring assembly.

5. To put the plate back in place there's a edge fit at the top of the frame. You put it there first before press fitting the plate back into the frame. DO NOT FORCE IT.

I've found that when reassembling, I had to angle the firearm slightly up (grip higher and pointed away from you) so that the hammer block stayed in place.

6. Tighten all the screws gradually (like when you change a tire) a little at a time till the plate is snug against the frame. Remove the yoke screw so you can put back the cylinder.

7. Lastly, fully tighten the strain screw. The mainspring will wobble out of place so you'll have to hold it tight until you fully tighten the strain screw. Replace grip.

I left out a lot of details since the assumption here is you're mechanically inclined. Also the assumption is you have the proper screw drivers or you'll bugger the screws.

A good reference (though does not apply to MIM revolvers) is Jerry Kuhnhausen, the S&W Revolver, A Shop Manual.

 

[scooter123]

My suspicion is that the hammer block may be just slightly bent, causing it to bind up either the hammer or the rebound slide. An easy way to test for this is to tighten the sideplate completely and in a very quite room flip the revolver upside down and back while listening for the hammer block rattle so many complain about. If it doesn't rattle you have found your problem.

One thing you could try to correct this is wet sanding the outer surface with some 400 grit wet-or-dry. Note, 5 minutes of sanding will probably only remove around 1 ten thousandth, so don't be surprised if you have to sit there wet sanding it for a good bit of time.

Another means of determining the problem area is by using Dykem Machinists Bluing and painting the sideplate with the Bluing. Then tighten the sideplate enough to just start that binding. Then cycle the action a few times and remove the sideplate. What you will see is that the Bluing will be scraped off in the areas that are being rubbed.

Link to die bluing. BTW I prefer Dykem because it's the only brand that I've found that dries completely without leaving a gummy feeling film. To remove it acetone works well.

Production Tool Supply

 

[tcon]

If it worked OK with the screws tightened down properly before and now it doesn't, I would look at the reassembly of the internal parts. Something is too high.

 

[PRM1]

It was a used gun, pretty mint, except that old oil had turned to varnish in places. I really don't know if the screws were tight when I brought it home or not. I gave it a good cleaning and that is when I noticed the problem.

It was put back together correctly and screws are in the correct holes.

Update

I removed the hammer block and put the plate back on and it works perfect. Put the hammer block back in and it binds when tightened. Although not visible, I am suspecting it might be bent just enough to be the problem. I am hoping I can get a replacement part from S&W.

 

[sw282]

Take the transfer bar out, then reinstall the side plate.. lf it doesn't bind,
Problem solved...lf it still binds, find a gunsmith

 

[PRM1]

My gun is a Model 60-4 and has the hammer mounted firing pin instead of the transfer bar system.

 

[VM]

My gun is a Model 60-4 and has the hammer mounted firing pin instead of the transfer bar system.

He probably meant hammer block

 

[Fishinfool]

I'm thinking you could probably straighten the hammer block using a flat, square surface to identify the bend? Maybe compare it to another hammer block out of another gun, if you have one?

Larry

 

[rbmorse]

Make sure the rebound slide is fully seated.

 

[bigggbbruce]

Make sure the rebound slide is fully seated.

Removing the side plate causes all the internals to move away from the frame. Check all internal components and seat them fully.

I really doubt the hammer block is bent.

 

[H Richard]

You didn't possibly "pry" the side plate up when you removed it did you? If so, there is a distinct possibility the side plate is "bent". That could cause this problem. That would call for a return to the factory for repair.

 

[bountyhunter]

"I removed the hammer block and put the plate back on and it works perfect. Put the hammer block back in and it binds when tightened. Although not visible, I am suspecting it might be bent just enough to be the problem. I am hoping I can get a replacement part from S&W."

problem solved

 

[bountyhunter]

You didn't possibly "pry" the side plate up when you removed it did you? If so, there is a distinct possibility the side plate is "bent". That could cause this problem. That would call for a return to the factory for repair.

Yep, that's the second most likely suspect. Maybe you did not, but it could have happened at some point by somebody else.

 

[bountyhunter]

If you still have the dragging with the new safety in:

You can strip all the oil out of the works and inside face of the side plate with carb cleaner or brake cleaner spray. Once dry, you can use a black sharpie to mark up the inside of the sideplate. Install and pull trigger then remove. You should be able to pick up the area that is dragging on something.