Gas Cutting the Arbor of the 1860 Army

[M. De Land]

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

I broke down my 1860,1858,1862 and Ruger Old Army. The 60 and 62 both have a small amount of gas cut erosion at cylinders end. The Ruger and 58 have none on the base pin and just a bit on the top strap.
The 58 Pietta has a machine cut across the base pin on top just about where one would look for gas cutting but upon close magnification examination of these it does not look like a gas cut but rather a machine cut as it is clean and sharp in shape with no signs of burned steel.
Never noticed the arbor gas cuts in the open framed guns as they are very slight.
Gas cutting in modern revolvers will slow down and stop after it makes the initial slot and will not reach a point of top strap failure with the exception of one high intensity revolver round I am aware of. I doubt it could ever happen in a percussion gun.

 

[Enfield58]

I also decided to take a look at all my revolvers. I have a 2nd generation Colt 1860 Army. I've shot it A LOT since I got it in 1981. I would hate to guess how many rounds have been put through it but probably more than its 1st generation counter parts.

The photos below show a cut but it isn't roughed up like my friend's Pietta. That made me think that maybe it was some sort of machine cut to keep fouling from building up on top of the arbor. After all, that is the only part of the arbor exposed to any gases unless there is a chain fire. Here are the photos of the arbor.

Like I said, this looks like a machine cut. So I took a look at my 2nd generation 3rd Model Dragoon. I have not shot it as much as the 1860 army since I only got it after the turn of the century. There is no evidence of any gas cutting on the arbor of the Dragoon. That is understandable because the 1860 Army was an improvement over the other models. I didn't take any photos of the Dragoon's arbor as there was no evidence of gas cutting.

My curiosity grew and I decided to take apart the 1858 Remington. I have had this revolver since 1979 and shot it more than the 1860 Army. Here are photos of the cylinder pin which shows evidence of gas cutting at the end of my thumb. The other grooves are the ones that I put in there to allow grease to remain on the pin so the cylinder could turn even with an accumulation of fouling.

My curiosity went from worry to concern. What if I was getting cutting on my precious LeMat? With great trepidation, I removed the barrel and cylinder. Oh the horrors! Oh the humanity! My beloved LeMat has a gas problem!

I've owned this revolver ever since the mid 1990s. I've shot it a lot as well. I got plenty of steel on the 1860 arbor and a cylinder pin on the 1858 Remington is easy to replace.

However, I want to be able to shoot the LeMat for another 20-30 years or until they put me in my grave or the nursing home (whichever comes first). Another 20 gauge barrel may be hard to replace.

Does anyone else have a LeMat that they have put a lot of rounds through? If so, are you getting this problem as well? Any concerns?

I'm also a little embarrassed as I didn't notice these problems before. It must be my eyesight and old age.

 

[Dphar1950]

If the cylinder goes on and off ok why worry.

 

[Enfield58]

If the cylinder goes on and off ok why worry.

I just wonder how many rounds it will take to compromise the steel of the shotgun barrel of the LeMat. Hopefully, I won't be able to fire enough rounds in my lifetime with that LeMat to risk a rupture in the shotgun barrel when I fire it.

 

[M. De Land]

I just wonder how many rounds it will take to compromise the steel of the shotgun barrel of the LeMat. Hopefully, I won't be able to fire enough rounds in my lifetime with that LeMat to risk a rupture in the shotgun barrel when I fire it.

Look at the intentionally cut lube grooves! They go all the way around and are deeper by far than the gas cut from what I can see. I doubt the cutting will progress much more as it doesn't seem to keep going after the initial cut it makes, even in my 44 magnums.

 

[Phil Coffins]

The gas cut groove is due to the shalllow and soft case hardening that the modern guns have. Try a gentle file cut in an unnoticeable spot on any replica and you will find it files very easily. Properly case hardened parts will have the file skate and not give more then a shiny mark. The core of the metal will still be malibale and stronge the hard skin is only a few thousands thick and resistant to gas cutting. The cost of affordable replicas.

 

[DOUBLEDEUCE 1]

That is truly interesting. I have seen the gas cutting on a few hundred modern service revolvers. The damage was so severe, those weapons were pulled from service. They were all basically the same age, and had thousands if not a few million rounds fired through each of them.

I would contact Pietta. Maybe they would replace the revolver. The least they could do would be to repair it and issue a cautionary warning.

How many rounds have been put through that revolver ?

 

[M. De Land]

The gas cut groove is due to the shalllow and soft case hardening that the modern guns have. Try a gentle file cut in an unnoticeable spot on any replica and you will find it files very easily. Properly case hardened parts will have the file skate and not give more then a shiny mark. The core of the metal will still be malibale and stronge the hard skin is only a few thousands thick and resistant to gas cutting. The cost of affordable replicas.

You might have something there as I have never checked the case depth on any of these reproductions. When I case color single shot rifle receivers it is file resistant but have no good way to measure depth. It looks to be something on the order of .005 or so when I have checked low carbon steel test strips. This from bending the strips until they break and then examining the depth from the end break. Only a guess though.

 

[Gun Tramp]

A bit off-topic here, but it is my understanding that the "coloring" on my beloved affordable replicas is a chemical treatment having nothing to do with true color case hardening. Might someone shed some light on this?

 

[Erwan]

A bit off-topic here, but it is my understanding that the "coloring" on my beloved affordable replicas is a chemical treatment having nothing to do with true color case hardening. Might someone shed some light on this?

That's right, this is decorative only and not any hardening by box in forge fire like before (long time ago), look at this : ...

Erwan.

 

[Gun Tramp]

Thanks Erwan!