1877 Colt Lightning timing problem???

Having excessive cylinder end-shake will mess with the timing on the 1877. Unfortunately it's not as easy to remedy as the SAA because the lack of a removable pin bushing. I have had luck in making a shim from a piece of steel feeler gauge to space the cylinder back towards the hand. It's kind of 'guerrilla-gunsmithing', but it works. I figured out the thickness by trimming and notching different thickness's of gauges and inserting the gauge between the frame and cylinder bushing, allowing the pin to pass through the notch. Now cycle the action, trying different thicknesses. This will usually bring the end-shake back into tolerance. This will open the cylinder gap a few thousandths, but not enough to be a problem. But sometimes the wear is so great that machine work will be required. You need to be careful not to loose the shim when you break the pistol down for cleaning. I lucked out on my latest Lightning in that it was still in spec. It was malfunctioning when I acquired it, operating on DA only, no safety or half-cock. I was thinking hand/sear spring was broken. I was pleasantly surprised when I opened it up that the spring had merely been installed incorrectly. The arm that tensions the sear was on the wrong side of the sear.

These little revolvers are not as much of a gun-smithing nightmare that most folk make them out to be. I love shooting mine. I've worked our a black powder, heeled slug round that shoots great. Your pistol look awesome Mitchsnap. I hope you get it up and running soon.

mitchsnap said:

If you could send me a pic of what you are referring to that would be great. This is a little new to me so I could use all the help I can get.Thanks for your response.

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Sorry I don't have pic capabilities at this time. But I think I can talk you through it. Now we're talking about the recess in the front of the frame opening where the cylinder pin passes through and the round extension at the front of the cylinder where the pin passes through. This projection is basically a gas seal to divert BP fouling away from the cylinder pin when the piece is fired. Cycling the action forces the cylinder forward against the frame and after a while it starts to wear. As the wear increases, the cylinder moves further forward away from the hand. If the wear gets too great, it will alter the geometry of the cylinder/hand interface and the timing will suffer. This fore and aft movement is end-shake. On a full-sized SAA, there is a removeable bushing. Over-sized bushing can be fitted to bring everything back into spec. But the 1877 doesn't have a removeable bushing. The pin rides directly in contact with the cylinder. This also creates wobble like movement. If the wobble is too great, machine work will be required. My 'guerrilla' fix won't do anything about the wobble, just the end-shake. Now, all that being said, lets move to the shimming. Get a cheap set of steel feeler gauges from the auto parts store. Remove the cylinder and pin. The recess in the frame is about .304" +/= .002" wide and about .635" deep(if it has the ejector, less if not, but you'll still need the length). Align the gauge leafs and clamp then together with a C-clamp. Now I took a cut-off wheel and carefully reshaped the ends to a width of about .305" and back to about .640". The cylinder pin diameter is just a few thousandths under .200". So next I'll cut a u-shaped notch into them, .200" wide, centered and to a depth of about .275". If you worked carefully, you now have a set of forked, 2-prong feeler gauges. Re-install the cylinder and pin and dis-assemble the gauges into their separate leafs. De-burr if necessary with medium sandpaper. Now the gauge should slip into the recess between the cylinder and the frame, the prong passing around the pin. Hold the gauge in place and cycle the action. Try different thicknesses. Usually one will move the cylinder rearward enough to allow the hand to work properly. When you find that thickness, you will cut a shim from that leaf. I'll start at the end that had the screw going through the bundle and drill that hole out to .200". Then I'll reshape the outside edge until it will sit down in the frame recess and the cylinder pin will pass through it. It doesn't have to be totally round, but it can be cut into a D-shape. This will locate it in the recess and not allow it to move. It's also easier to remove and replace during cleaning.

Questions?