Hammers on Lifter gun not set right

[Taylor Heiner]

So I have an 1876 lifter gun that I I took apart because the left hammer was not at the correct position, it was always resting against the firing pin rather than having a bit of clearance, causing the firing pin to stick out a little at the breech. After I took it apart I saw there was a little bit of wear on the resting pin and mainspring so I tried to shim it but that didn’t fix the problem (it is not as thick as it appears in the photos and I will probably be removing it soon). I checked all the parts and I don’t see any bent parts compared to the right side which is fine. The only thing I can think of is that the hammer shaft must have spun in the press-fit. Has anyone run into this before? If it is the press fit, is there any way I can make it so it doesn’t slip again without welding it? This is a low-grade gun and I really don’t want to be dumping lots of money into it on complicated repairs.

[Brian Dudley]

Nothing LOOKS wrong from the pictures. But the hammer should be sitting back in the rebounded position like the right one. It is not really possible for the hammer to “spin” on the tumbler shaft as it is a tapered square shaft. They can looses up some with wear, but not move that much.

[Taylor Heiner]

Ok thanks. I was mainly considering buying another left hammer and heating & bending it to the correct position. I don’t want to do it on this hammer because it will probably ruin the original case hardening and I personally don’t have the capabilities to re-case harden it. All numbers match so it would make me feel better if it was a replacement part that I bent

[Aaron Beck]

is it possible the left hammer isnt original to the gun?

[Taylor Heiner]

No, all numbers match. Serial 8342

[Phillip Carr]

Is there something on the end of the main spring?

[Jim DiSpagno]

That’s what it looks like to me Phil. That mainspring looks to have been altered/repaired in some way. That would alter the hammer position somewhat

[Brian Dudley]

The OP said he tried a shim to see if it helped. That is what you are seeing.

[Jim DiSpagno]

Thanks Brian. Maybe a new mainspring is the answer in

[Taylor Heiner]

I dont think it’s the mainspring, because when I put that shim in it helped a little but not much, not enough to fix it. Based on what I see, the problem is from the hammer shaft to the linkages, because the hammer itself is the same shape as the right, it’s just that when I line up both the square ends on the hammer shafts the locks point in different directions. So either that whole hammer shaft got twisted somehow, the shaft isn’t lined up correct/slipped on that main linkage (which I thought was the problem), or the linkages are bent somehow. None of these ideas seem plausible

[Taylor Heiner]

Update: I just removed the tumbler and this is what it looks like. The shaft itself is not twisted so that crosses that off. I still can’t tell if that shaft and tumbler are made as one piece or if the shaft is fit inside. I know on some guns that shaft is threaded but I don’t want to mess around and break anything. Does that shaft look to be lined up correctly?

[Brian Dudley]

The tumbler is all one piece.

[Aaron Beck]

Maybe the square shaft or even hole was built up with weldment and when fit back the angles were just a bit off.

[Taylor Heiner]

Quite possible. This is the tumblers side by side. The picture doesn’t do a great job but you can see the square shafts are off. All the rest of the geometry is correct

[Dean Romig]

Do they both have the same three-digit number stamped on them?






.

[Arthur Shaffer]

The last picture shows the problem. Now as to the fix.....

[Taylor Heiner]

There are no numbers on either of the tumblers, the closest numbers are on the bridles, locks, and hammers and they all match

[Dan Steingraber]

Just a thought but I'd check the firing pin for proper length and shorten it a little if it would still function properly. It may not be the original firing pin.

[Taylor Heiner]

Update: I definitely found the problem. Upon closer inspection, There appears to have been a stress crack at the base of the square shaft and that weakened it and allowed it to shear/twist at the base of the square end. Only the end is affected, and I can definitely see a small twist at the very base. I can probably repair this but does anybody happen to have a left tumbler laying around they would be willing to part with? That sure would be easier.

[Brian Dudley]

Good to see you found the issue.

I have many tumblers on hand.

[Taylor Heiner]

Sweet. Just sent an email.