Gas Cutting the Arbor of the 1860 Army

[Enfield58]

A friend of mine has a problem with the gas cutting the arbor of his 1860 Army. The attached photos show how far the problem has progressed.

I have a 38 year old 2nd generation 1860 Army that has been fired a lot. Yet, I haven't experienced this problem.

His 1860 Army is a Pietta. I read on another forum that it might be a royal PITA to remove and replace the arbor. Is it really that difficult?

I thought that perhaps he could put a weld in the groove that's developed in the arbor. Then file/dremel over the weld enough that the cylinder can pass over it when being removed or installed.

Then, perhaps, the weld would be stronger than the surrounding metal and prevent any additional gas cutting.

Does anyone have any other ideas?

Thanks in advance.

 

[Greasecookie]

Wow, I thought I shot my C&B revolvers a lot. Might be time for a new gun. But, TIG welding would work to fill the canyon. He might want to check his barrel cylinder gap.

 

[Enfield58]

Wow, I thought I shot my C&B revolvers a lot. Might be time for a new gun. But, TIG welding would work to fill the canyon. He might want to check his barrel cylinder gap.

The gap is tight enough. I’ve seen him shoot it and I have as well.

I’m not a welder and so I don’t know. Would the weld be harder than the surrounding metal?

 

[Greasecookie]

Depends on the filler metal and procedure, TIG welding has a small heat effected zone, but any hardness difference wouldn't make a functional difference.

 

[Gun Tramp]

Chamber diameters too large in relation to bore size.

 

[Enfield58]

Chamber diameters too large in relation to bore size.

You might be on to something. IIRC he’s always had a little too much play in his original cylinder. I never thought it would be that much of a problem but he’s had trouble with inconsistent ignition. That’s even with Slix-shot nipples.

He’s got a new cylinder that doesn’t exhibit as much play and the ignition is consistent.

Could the excessive play in the old cylinder allow too much gas to escape onto the arbor?

The .451 balls were tight in the chamber and shaved lead. So I don’t think the chambers were too large.

 

[SDSmlf]

Have to question the ‘steel’ used to manufacture that arbor. As far as a repair, may want to see if there is anyone doing ‘micro’ welding with a laser welder nearby. A very precise and controllable process.

 

[bang]

Bit of a task but change the arbor. Mine are 20 plus years old and do not show any signs of cutting. Steel definitely in question. Just out of curiosity what is the load used and is the lead pure lead.

 

[Enfield58]

Bit of a task but change the arbor. Mine are 20 plus years old and do not show any signs of cutting. Steel definitely in question. Just out of curiosity what is the load used and is the lead pure lead.

22 grains (by volume) of Pyrodex P and Hornady .451 round balls.

 

[bang]

22 grains (by volume) of Pyrodex P and Hornady .451 round balls.

Wow, I've been using Pyrodex P over 20 years and never had anything like this. Load is good. Have only read about arbor replacement. If you go that way once you get it out tap the lock pin hole for a set screw once you get the arbor installed That way you can install it with locktite and not have to worry about any possible loosening. Things like that always seem to work best first time round, IMO. Seems threads have to be started clocked to position on frame and arbors the same on all so only adjustment would be very minor trim to get torque range to position. From reading once the gun is completely disassembled you located the lock pin in hammer valley. Punch mark center. Then the frame can be placed on recoil shield straddling arbor which will put the lock pin inline to drill out using drill press. After that secure in padded vice with a close to snug fit bar in wedge slot and apply pressure while applying heat. Can't remember if the replacement arbor already has the lock pin slot or not but if not back to the drill press. Was suggested to tap for 6 or 8 dia set screw or which ever size closest fits the hole size for tap drill size. To me the job sounds worse than what it is.

 

[ASMman]

Common, this is why Colt went to a bushing system on the 73's. I've read articles where they put a bushing into a Remington, but have seen nothing on a Colt. I guess a micro welder & something hard to fill it in, then I'd polish it a little undersize so not to wear the cylinder.

AntiqueSledMan.

 

[sussexmuzllodr]

A friend of mine has a problem with the gas cutting the arbor of his 1860 Army. The attached photos show how far the problem has progressed.

I have a 38 year old 2nd generation 1860 Army that has been fired a lot. Yet, I haven't experienced this problem.

His 1860 Army is a Pietta. I read on another forum that it might be a royal PITA to remove and replace the arbor. Is it really that difficult?

I thought that perhaps he could put a weld in the groove that's developed in the arbor. Then file/dremel over the weld enough that the cylinder can pass over it when being removed or installed.

Then, perhaps, the weld would be stronger than the surrounding metal and prevent any additional gas cutting.

Does anyone have any other ideas?

Thanks in advance.

View attachment 19748 View attachment 19749 View attachment 19750

Taylor and co. $17.50 for the arbor.
SM

 

[ASMman]

I guess to remove arbor, you first need to remove the stake pin. Then it's just a matter of threading it out. Now would come the fun stuff, thread in a new arbor, get the wedge hole to line up with your barrel (professional's do it all the time), and drill in a new stake hole (I'd drill & tap and replace stake pin with a set screw). Should be a piece of cake. (see why I'd repair it).

AntiqueSledMan

 

[Zonie]

I'd just file the area so nothing was sticking up above the outside of the arbor (if it is) and forget it.

Welding it will distort the arbor and really, because the arbor is more than strong enough to deal with the loads that are put on it even with the damage. It won't be worth the trouble. (The arbor is solid steel in that area so it is strong enough even with the damage.)

 

[Pete G]

I agree with Zonie. Smooth it and forget it.

 

[M. De Land]

Wow, I've not seen a gas cut arbor before. I notice the gas cut is no deeper than the lube grooves cut in the arbor and does not circumvent it either. Plenty of metal left for more than enough strength in the arbor.
This is more of a eye sore than it is a danger to safe firing. I'd leave it alone or change the arbor if it bugs you to much.

 

[ZUG]

I'd clean it up with a file & emery paper and leave it alone. I'd also buy a new gun and shoot them both. When the first one bites the dust save it for parts if any are worth saving.

 

[Gun Tramp]

I also agree with Zonie. But, why is it happening? You mentioned that the cylinder has been replaced. Is it possible it is not indexing correctly and a now-misaligned slug is being forced into the barrel causing higher pressure? Gas-cutting of the top strap is not uncommon on high pressure modern unmentionables...

 

[Enfield58]

I also agree with Zonie. But, why is it happening? You mentioned that the cylinder has been replaced. Is it possible it is not indexing correctly and a now-misaligned slug is being forced into the barrel causing higher pressure? Gas-cutting of the top strap is not uncommon on high pressure modern unmentionables...

The cutting occurred with the old cylinder which had some play in it.

Now that I think about it, that could have been the reason.

When the powder ignited to push the ball out of the chamber, the cylinder moved back enough under recoil to create a too large of a gap for the gas to escape and cut into the arbor.

That’s my theory.

The new cylinder has not been on there long enough to determine if anymore cutting is taking place.

 

[Erwan]

I saw that on Remington but never on a Colt ....
TIG welding and finish with a file and that will normally do the job, I think...