Martini Henry rechamber (.450NE or similar)?

[Son of Dorn]

This isn't strictly speaking a precision rifle-related question, just a vintage one. I've had a thought and wanted some feedback. Is it possible to rechamber a Martini-Henry rifle from 577-450 to something stronger, say .450 Nitro Express or another big-bore calibre? I've seen some folks who've done Sharps rifles from .45-70 to .450NE and I expect that with the larger-calibre Sharps one could try to do the same for the other NE rounds; maybe with a Winchester 1885 High-Wall too. But what about a Martini-Henry? Not saying I would or will do it, just wondering if it can be done (and safely function, at that).

Thank y'all,
Son of Dorn

 

[MK20]

I saw one once (May have been a commercial reproduction) chambered in 416 Rigby.

 

[Son of Dorn]

I saw one once (May have been a commercial reproduction) chambered in 416 Rigby.

Hmm. Wouldn't be my first choice and I question how well a rimless cartridge would work, but it's some food for thought.

 

[MK20]

Do you already have an action?

 

[Son of Dorn]

I don't have one, no. Wish I'd gotten a couple a few years back, but missed out. Just had the idea for it the other day and thought I'd toss it around.

 

[MK20]

If you need an action I can source one for you really cheap right now. Probably about 150 bucks.

 

[Son of Dorn]

Thanks but atm I'm tied up with some other projects I wanna work on first. And until I'm positive I can get what I want out of a Martini-Henry, I think I'd be better off setting it aside for later. But if I change my mind and you can still help me out, I'll let you know.

 

[RPN]

45-70 is about as long as you can go without modifying the breech block, or using a very sharply tapered cartridge - and given the stress is taken by the hinge pin rather than the receiver, I don't know how high I'd want the forces involved to get.
That said, I made a 45-70 up 35 years ago - new forend, express sights, the whole 9 yards and had a blast with it. Occasionally wonder what happened with it after I sold it.

 

[Son of Dorn]

45-70 is about as long as you can go without modifying the breech block, or using a very sharply tapered cartridge - and given the stress is taken by the hinge pin rather than the receiver, I don't know how high I'd want the forces involved to get.
That said, I made a 45-70 up 35 years ago - new forend, express sights, the whole 9 yards and had a blast with it. Occasionally wonder what happened with it after I sold it.

I figured cartridge length might be an issue. I could probably go with a .45-70 just for something fun to play with, and acceptable for some US game should I ever want to use it, but I was looking at the Nitro Express (or possibly a .400 or .404 Jeffrey despite being rimless) in the event of having something beefier for African game one day. So maybe I'll look back at the Sharps/High Wall idea.