What's the easiest way to polish cylinder chambers

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1sailor

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I don't own a Dremel although I could buy one (I should have one anyway I guess). another thought was emery cloth wrapped around something. I'm having some issues with a M686+ with the recoil forcing the fired empties back against the recoil shield and when an empty comes up to the next in line position it makes it almost impossible to fully cock the hammer unless I actually push the fired round back in place. Even with unfired rounds it can cause some grittiness. I'm hoping that polishing the chambers will take care of the issue.
 
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Sounds like you have an early version that is in need of the factory recall.

If it is a no-dash or a -1 without the "M" stamp on the frame it needs to go back to the mother ship.
 
Well I'm glad I asked first. I had figured it would be no big deal to do. This is actually a newer 686+. There's a retired smith that lives not too far from me so I'll give him a call and see what he has to say. Otherwise it's a half day round trip to my closest gunsmith. Still I suppose that would be better than screwing up my cylinder. I suppose I could also just send the cylinder to somebody reputable who hopefully wouldn't have to put me on a 6 month waiting list. Anyway, thanks for the heads up on the Dremel.
 
I use a maroon Scotchbrite pad wrapped around a 22 cleaning brush. Cut a small rectangle out of the SB with scissors and put the brush in a straight piece of cleaning rod. Put the cleaning rod in the cordless drill. Pretty hard to do any damage with that setup.
 
Whatever you use, keep your power driver moving in and out to prevent cutting grooves and wallows in the chambers.

A piece of wood dowel close to chamber diameter makes a simple mandrel. Make a vertical cut in the front half of the dowel to capture a piece of 600 - 800 sand paper or Emory cloth. Put one end in the dowel cut and wrap a strip around the dowel the opposite direction of drill rotation until it's a snug fit in the chamber. Move in and out as you spin it, don't over do it; just until you see a uniform polish in he chamber. Only takes a couple of seconds per chamber.
 
Hondo44 said:
Whatever you use, keep your power driver moving in and out to prevent cutting grooves and wallows in the chambers.

A piece of wood dowel close to chamber diameter makes a simple mandrel. Make a vertical cut in the front half of the dowel to capture a piece of 600 - 800 sand paper or Emory cloth. Put one end in the dowel cut and wrap a strip around the dowel the opposite direction of drill rotation until it's a snug fit in the chamber. Move in and out as you spin it, don't over do it; just until you see a uniform polish in he chamber. Only takes a couple of seconds per chamber.
Click to expand...

Any type of lube suggested for this method?

Thanks
 
Use very little oil or just don't use any oil at all.
None is really needed, and if any oil leaks into the ejector shaft at the rear or cylinder yoke at the front you could have problems with the abrasive doing damage or causing the cylinder to stick or drag.

After polishing clean the chambers thoroughly, starting with a couple of dry patches then with a solvent.

Note the above, this takes only a few seconds, depending on the abrasive used. Don't over do it, The chambers don't need to be bright and shiny, just smooth.

For the abrasive you can use Crocus cloth which usually comes in strips, VERY SUPER FINE wet or dry type sand cloth, or fine Scotchbrite pads.
Super fine wet or dry sand cloth and Scotchbrite pads can be bought at auto supply houses where it's sold for car painting.

On a stainless gun DO NOT use steel wool. Steel wood can embed tiny particles into the stainless and the carbon steel wool will rust and ruin the surface.
 
I just finished making sure the chambers were absolutely clean and then inspected them under good light and I'm actually kind of surprised to see that the chamber walls look bright, shiny, and smooth. I had expected to see some roughness or some course lines or something at least.
 
But that now begs the question, If it's not rough chamber walls then what exactly is causing the issue. Which is not to say that the chambers cannot still be the problem. Primers are not rubbing, nothing under the star extractor and empty it is as smooth or smoother than any other revolver I own with the possible exception of my M27. Not rubbing on the forcing cone, none of the other usual suspects I can think of. I can literally see the case rim hanging it up and relieve the issue by pushing it in.
 
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It may be too large of a gap between the rim of the fired case and the recoil shield, or brass with unusually thin rims. I'd try different loads (ammo/brass makers too), and if the problem persists there is always the lifetime warranty on which to fall back.
 
Honestly I don't trust the company to be able to reproduce it. In all likelihood and the gap certainly isn't too loose. it would come back as "within spec". Half a dozen different types of brass. I'll keep dinking with it. I'll take it out again loading only 6 rounds at a time and starting with the empty chamber at the top. See what it does.
 
The reason we don't want any oil in the chambers is because it lets the case slip out back against the recoil shield. Then they bind when trying to rotate the cyl. So if the chambers are polished bright and shiny it causes the same problem. Your's could be too shiny. Possibly a former owner (if you're not the original owner) over polished them.

When you sand the chambers you're actually putting a fine cross hatch on the walls of the chambers. This acts to grip the brass case as it swells under firing and grips the cases in the chambers.

Too course of a cross hatch (and pits or uneven chamber walls) actually make cases too hard to extract. That's why you don't want to use finer than 800 grit or so, or courser than 600.
 
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It's possible that in my attempt to recreate the issue I have that I've created an artificial problem that's mimicking the symptoms I'm getting in the field. I'm going to load up a couple hundred rounds and see if I get the same results during live fire (if it ever stops raining anyway). Next time it binds up on me I will (using great caution to keep the muzzle pointed in a safe direction) see if the same thing is happening that I'm seeing here at home. The fact that there are no problems at all when the pistol is empty makes me think that I am on the right track however. I'd also like to thank everyone for their replies.
 
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