Lee-enfield SMLE to .45-70 Conversion

Seacowboys · Feb 10, 2018

I am new to this forum and in fact, am a Southerner living down in Mobile, Alabama but a friend on another forum recommended this would be a good place to get a bit information about a project I want to under-take. I have a .45-70 in a double rifle, a Henry Golden Boy, and a Savage 219B line-launching gun but really lie a bolt-gun in that caliber. I cast a lot of 500 gr slugs a while back for a .45-120 I had but decided that was just too much powder. I bought a decent Lee-enfield SMLE Mk1 commercial model today and am thinking about rebarrelling for .45-70. I understand magazines can be modified for the round and the bolt-face doesn't require change, from what I've read on a couple of gun smithing forums. Has anyone here made this particular conversion? There was one for sale on Gunbroker last week in Utah but I got sniped and let it get away. Thanks in advance.

MountainBear · Feb 10, 2018

Haven't done that one. Did a Siamese Mauser, but feeding can be tail-chasing obnoxious.
I know Gibbs did this conversion years ago on the SMLE. The rim diameter on the .303 is .540, while the .45/70 is .608". So a little opening seems necessary, but it's possible I'm missing something. I would assume the magazine alteration would be to the follower.

I look forward to watching your progress!

Seacowboys · Feb 10, 2018

I was reading about the Gibbs conversions, Navy was selling some mags they made for them. Thought about using one of my 98Ks but found the enfield today at a show for pretty cheap and tight and somebody will want those mausers one of these days just for the nazi markings.

Argonaut · Feb 10, 2018

Siamese Mausers were the common rifle for this conversion but I have seen P14 Enfields done in 45-70. I have one done in 458 Win Mag in a 20" Manlicher carbine.

MountainBear · Feb 11, 2018

Seacowboys said:
I was reading about the Gibbs conversions, Navy was selling some mags they made for them. Thought about using one of my 98Ks but found the enfield today at a show for pretty cheap and tight and somebody will want those mausers one of these days just for the nazi markings.

The Siamese Mauser is a bit different than the 98k. It already used a rimmed cartridge, so the magazine and bolt face were already set up for it. The feed rails need massaging to get the feed just right. I have not seen someone take a standard 98 and convert it, although I'm sure it's possible.
If I were starting one today, I would likely go the SMLE route, same as you. There are plenty of butchered guns already out there to play with. A No. 1 mk. III would be my choice, because of the cleaner receiver.

Argonaut · Feb 11, 2018

There is a reasonably priced Siamese Mauser 45-70 conversion on Gunbroker right now. Things have become so expensive........just the cost of a custom rebarrel can be close to 1000.00 it would be cheaper to start with one that the hard work is done on and modify it to fit your needs.

orygun · Feb 11, 2018

When Gibbs was advertising their Quest 45-70 SMLE conversion I tried to buy one. Too bad I picked a crappy dealer and almost lost my deposit. After I waited on that dealer for a few months my hunger for one faded and it wasn't too much longer before Gibbs folded.
A Mauser action would be stronger than the SMLE, but it still would have been a potent woods gun.
If I tripped across one of those Quest carbines today, I'm sure I'd try to take it home.

Seacowboys · Feb 12, 2018

I might just buy that one on GB, it looks like a very nice rifle but I'll probably still try this conversion because , well I sort of want to rechamber and barrel a Lee-enfield. That's sort of the point of a hobby gunsmith that doesn't really hunt or need the the thing; you build it because it's there.

MountainBear · Feb 12, 2018

Another entertaining caliber to consider if you are wanting to play with the Enfield would be the .458 x 2 American. Another fun thumper caliber. Either way, playing with the SMLE is still a worthwhile pursuit.