Antique caliber change

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aerobeast

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Good Day CGN,

I have a question regarding caliber changes to antique pistols. I am kind of new to this, so this may be a dumb question.

I would like to change a 1892 41LC to a usable caliber. I understand that modern smokeless cartridge pressures are too high for the mild steel construction. But consider the following:

Could I lower the caliber of the .41lc to something like a 22 WMR? I pick this cartridge because the case lengths are very close. If not 22 WMR, then something smaller but not on the forbidden antique caliber list. I would do this by modifying the cylinder bores with press fitted titanium inserts, do a barrel change or steel barrel insert to 22 caliber and modify the firing pin to strike the edge of the rim.

Would this insert and the new barrel help the revolver deal with the higher pressures? Or is there more to it than that?

Could I also heat treat that old steel with a more modern controlled heat treat process to enhance the material properties?

And how much modification can be done to an old pistol before it's no longer considered an antique?

Thank you

Edit: the choice of titanium for a chamber insert would be a bad idea, as titanium does funny stuff when hot! So perhaps a steel would be used.
 
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41 colt is available at some of the site sponsers Now just saying---please do not wreck an antique by changing calibre, sell it and buy a revolver in calibre of choice. AFAIK changing to .22 of any variant will put this back to restricted status. The reason I say this is that I love antique firearms and they are not making any of these anymore.
 
.22 mag is fine.

It's a troublesome conversion and would add weight to the gun. The 1892 had issues as is...ymmv

Edit to add: why not .38spl?
 
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Thank you for all your responses so far!

I agree that 41lc is a useful load, and I read that in some respects, it has more stopping power than a 38special. I would also be interested in reloading 41lc.

However,

I have already made up my mind that I am going to modify one antique to shoot modern off-the-shelf loads. I think modernizing one of these antiques again is also a great gift for something that old! There are lots of antique cars out there with modern engines, and although they are still not practical as a commuter, they are much more convenient! The changes I am describing would be keeping as much of the firearm intact as possible to achieve the goal of shooting modern cartridges.

But all philosophy aside, my question from my OP was more of a scientific one...by making the modifications as described above, with the inserts/barrel, theoretically, could one of these old gals be given a new life to shoot a modern cartridge safely?

https://www.youtube.com/watch?v=BIh1Sm4DyAE
 
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Deuce-deuce said:
.22 mag is fine.

It's a troublesome conversion and would add weight to the gun. The 1892 had issues as is...ymmv

Edit to add: why not .38spl?
Click to expand...

Yes 38 special is another caliber that could be 'downsized'. I love that round and I have an old restricted s&w k38...My thinking is that the round would have to be 'downsized' enough that the insert's walls could be large enough that it adds to the strength of the chamber while the significantly smaller cartridge has a lighter pressure.
 
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aerobeast said:
Good Day CGN,
Could I lower the caliber of the .41lc to something like a 22 WMR? I pick this cartridge because the case lengths are very close. If not 22 WMR, then something smaller but not on the forbidden antique caliber list. I would do this by modifying the cylinder bores with press fitted titanium inserts, do a barrel change or steel barrel insert to 22 caliber and modify the firing pin to strike the edge of the rim.

Would this insert and the new barrel help the revolver deal with the higher pressures? Or is there more to it than that?

Could I also heat treat that old steel with a more modern controlled heat treat process to enhance the material properties?
.
Click to expand...

I think it would be a royal pain to convert from centerfire to rimfire. If you have the ability to do the work that you suggest, yourself, you also have the ability to make sizing and forming dies to create a shell which meets the antique criteria (ie is not on the no-go list) I think the biggest concerns in terms of pressure are the firing pin hole, the cylinder wall and the strength of the frame itself to resist stretching. I think 22 magnum would be a bad choice partly because I suspect that you could also chamber 22 long rifles shells in the gun. The value of heat treating steel in part requires a suitable ratio of carbon to iron in the steel and if your gun is made from mild steel, heat treating would have little effect. Unless you are very knowledgeable of heat treating, you could easily create problems rather than solve them. I think you would be far better to use removable chamber inserts (perhaps loktite them in to reduce the risk of someone putting a 41 shell in) and to rebarrel the gun and save the old barrel, unless the bore is like a sewer pipe

cheers mooncoon
 
At the end of the day, it is your pistol and you can do want you want with it. The two main things to watch when shooting modern ammo in an older sixgun are a) chamber strength and b) frame stretch. I doubt that (b) is going to be a factor, given what you are thinking of, so (a) is your main consideration. If you keep chamber pressures near what the 41 Colt had, or even the 45 Colt, you should be fine. As long as you keep the original frame, it would still be classified as an antique *provided* it was not converted to a non-antique caliber. Another option is to modify the chamber to accept modern 41 caliber bullets with the normal lube grooves, and have Accurate Moulds make you a custom mould for such a bullet (same price as a non-custom mould from him). I'm not familiar with the chamber specs for the 41 Colt, but all that might be involved is to ream the forward part of the chamber to be the same diameter as the rear portion of the chambers. Don't take my word for it, though.
 
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