Converting a Mosin Nagant to .45-70

Two home gunsmiths, Chapaev and Voland, have been working on converting two Mosin Nagant rifles to use the .45-70 cartridge. Their almost completed rifles have a 3+1 capacity, 16.25″ barrels and fiber optic sights.

It was no easy task with a lot of modifications required. The pair extensively documented the process on their blog Pharmory.

One of the rifles being test fired.

I think Captain Mosin and Mr Nagant would approve.

Steve Johnson

Founder and Dictator-In-Chief of TFB. A passionate gun owner, a shooting enthusiast and totally tacti-uncool. Favorite first date location: any gun range. Steve can be contacted here.


  • Mechman

    …I’m horribly tempted to do this.

  • Komrad

    If they sold them, I’d buy one. It’s always cool to see old military rifles with different calibers, so long as the rifles don’t have much or any historical value. I’d never try anything similar with an Arisaka with the mum, for example.

  • S&Wbt

    any idea why they blurred out their faces?

  • JMD

    I applaud their efforts, as the end results look great. Having said that however, ouch! Those things must recoil really hard.

  • Ladyfox

    Pretty nicely done and nothing like some of the bubba jobs I’ve seen on some Enfields and other Nagants. Granted some will ask why and I’d ask why not? Things like this are what move the industry and our hobby forward keeping it alive for those future generations.

  • WeaponBuilder

    I’ve gotten a chance to meet these two young Home Smiths once a few years ago…

    They are quite talented, and quite adept at thinking outside the box.

    These are certainly quite nice builds!

    Congratulations, Guys!

    Chapaev, your brass might also be sticking in the chamber due to a possible hidden burr when the chamber was reamed. This can be caused by slight, imperceptible tool chatter with the chamber reamer.

    Polishing the chamber ever so lightly with a chamber brush, and polishing compout may remove any light burrs, and aid in smoother extraction.

    Great builds!

  • Will

    7.62×54 kicks enough on its own, now .45-70? crazy.

  • Jeremiah

    Very cool.

  • Moriarty

    Interesting, but given the extent of gunsmithing necessary, most people would seem to be better served with a Guide Gun.

  • armed_partisan

    That is awesome! Finally, a purpose for the Mosin Nagant.

  • zincorium

    Seems like they could use the extended magazine modification for the Mosin you reported on a while ago. Three rounds isn’t a lot.

  • Very cool. I just began playing with the .45-70 and I’ having a blast!

  • GySgt_Barnes

    Will it chamber .410?

    • AL

      It would be ggreat if it would ,,but i dont think it will the 410 has a a size more like the .45 long colt.

  • Francis X

    Needs low light shots! The flame has to be massive.

  • redjeepgirl

    This is just begging to be suppressed with some low velocity rounds. I’d buy this.

  • I know that Finnish shooters wildcatted the heck out of the basic 7.62x53mmR case, necking it down and all the way out. Of course, we have better access to .45-70 brass here. Another idea would be to rechamber it to .475 JDJ (a .45-70 case with its body taper removed), or one of its shorter offshoots, the .475 Linebaugh or .475 Linebaugh Long.

  • Why’d they bur out the face? That jest makes it look creepy. But nice rifle, OLD SCHOOL!

  • Charlie

    Why 16 1/2 inch barrels? Doesn’t anybody like rifles any more? The original Springfield Trapdoor had a 30″ barrel. Even the cavalry carbine was 22″. If they’re going to use these as guide guns, they better smooth out the action or basically they will have only one shot. Gibbs Rifle Company converted British Lee Enfields into 45-70 carbines, but still had a 21″ barrel. Personally, I wouldn’t want to shoot a 45-70 caliber rifle with less than 24″ barrel.

  • Kyle

    I’ve always been tempted to rechamber the Mosin Nagant in something more…modern. Like, .308 or the like. With a 16.25 inch barrel and hi-viz fiber optic sights, it’d be a handy brush gun.

  • howlingcoyote

    Advanced Technology makes a synthenic stock for the Mosin-Nagant and I think RamLine does too.
    It would be interesting like the other writer wrote, in 475 Linebaugh. What about the 500 S&W or the 50 Alaskan? Or 50-110 Wcf.

  • I think it would have been better as a rifle than a carbine.

  • George

    I have a Marlin Guide Gun with 18.5″ barrel – that thing is a pussycat and I can hit a 6″ circle at 100 yds with no issues using the peep sights. Its a super fun gun to shoot – some people are looking for a convenient rifle to stow and take along in a pinch.

    I dont think the 45-70 will produce near as big a fireball as the 7.62x54R – the powder types are markedly different and the 54R is designed for longer barrels. This means its still burning at 16″ and will have a huge muzzle flash from the shorter barrels.

    I love the ingenuity. More power to them!

  • Giving it more thought, a conversion to .444 Marlin would probably require less cutting. You could also choose any of the .444 Marlin-based wildcats, like the .375 JDJ.

  • Rob

    Sweet jesus. Do want.

  • Dusty

    What’s the point? to make it more expensive to shoot and no more useful?

  • Ed Onder

    I like it in 45-70, but 444 Marlin would be interesting as I have a lot of 444
    brass and bullets. Very interesting idea with so many of them out there if it could be done at reasonable price it would be even better. If they go into production with this idea please e-mail me. Great idea.


  • Steve G.

    How much to buy one?

  • Ahnkochee

    I much prefer a 20 or better yet 22 inch barrel in 45/70. 16.5″ not enough barrel to burn the majority of the powder capacity of the 45/70 thus wasting powder and power potential of this cartridge resulting in excess muzzle blast, and muzzle flash.

    I own a Lee Enfield in 45/70 with a 22″ barrel and this rifle IS FUN.


    • There were a lot of .30-06 conversions offered by gunsmiths after the DCM began selling the US-made Mosin-Nagants that were never delivered due to the Bolshevik Revolution. As you can imagine, quality varied dramatically.

      • Tim

        I dont think that you would actually know if it fed right or not…… You dont strike me as a person that would know the difference.. Il give ya 50 bucks for it ok.. 🙂

  • Tim

    Most of this discussion is just riddled with semantics because “you like what you know” and thats just human nature. I can pop your bubble with a 45-70 just as easily as I can with a little .223 and I might even pop you good with a .22 LR from Wal-Mart at the same distance.. .. Just saying .. Get to know your weapon well and stock your ammo accordingly.. THE END!!!

  • Tom

    The .378 Weatherby magnum case head fits into the Mosin Nagant bolt face like they were made for each other. The .378 case is too long for the M-N action, but could be shortened. Just an observation, for what its worth.

  • mike

    What modifications are needed for Lee Enfield mags to convert to 45/70?

  • flightmedic182

    I think they are pretty cool conversions. I’m currently building a Mosin Nagant plinker, I’ve shortened the barrel to 22″, threaded it 5/8 x 24 and installed a nice muzzle brake, cut and lapped an 11 degree target crown, smoothed out the trigger (as much as possible, saving for a Timney), drilled/tapped/mounted a 4-16×40 scope, turned down handle with a tactical bolt knob I turned on the lathe, and modified an old, beat up military stock to free float the barrel and be a bit more comfortable (until I finally break down and order a Boyd’s thumbhole for it). I also glass bedded the action, installed a Blackhawk bipod, abrasive blasted and gave it a nice matte black Duracoat finish. I’m finishing up some minor stock work tomorrow, and I’m hoping to get it to the range this week for a shakedown (I shot it quite a bit in it’s stock form, so I know functionally it’s all good). Why, some people ask, am I putting all of this work into a 1933 $89 rifle? Well, because I can. It’s not a historically significant rifle (other than it being a Mosin), the base price was super cheap, it was already half “bubba’d” when I bought it, I’m doing all of the work myself in my home shop, on my own time, and most of all, it’s been just plain fun! After it’s all said and done, I’m going to have about $300 in it without a new stock and timney trigger. Sure, it’s probably not going to out shoot my accurized Remington 700 7 mag at 1K yards, but I bet I’ll be able to get it to MOA out to 7-800 with some careful load development and if I do my part as the shooter. And if not, OH WELL! I’ve had an insane amount of fun, and learned a few things doing it. I have a few spare barrels and the original stock, so I can always go most of the way back. I’ll post some build pictures on my facebook after it’s done, maybe it will inspire a few people to take the plunge and build what they want. God bless, and Happy Veteran’s Day to our service members (past and present), every American owes you a great debt of gratitude.

  • creatinewarrior

    haha, Chapaev uh? where is your sword and horse, Mr. Vasily? a Mosin would be cool in a 4570 if somebody would charge to do it.lots of people would pay.

  • Whit Johnstone

    Actually I don’t think that Captain Mosin would have approved of this conversion. The .45-70 is exactly the sort of large-caliber round that was looking very long in the tooth in 1891, and in fact it was the 7.62x54r that rendered the .45-70 and all similar rounds obsolete for military use. The 7.62x54r is a more sophisticated round, designed from the start with smokeless powder in mind, and with a much flatter trajectory, even with the original round bullet. The US Army would not have a cartridge that equaled it until the invention of the .30-06 some fifteen years later. In other words this conversion, though interesting, is a step backwards.

    • Yuuzhan

      its also one of the most versitile rounds out there. load it from .45 acp levels all the way up to 4k ft lbs.

    • matt

      Do you really think they did these conversions with hopes of the military adopting them? As a sporting cartridge you cannot compare the two cartridges. Its like trying to compare a Kenworth to a Porsche 911. Maybe these two guys wanted a 45-70 and didnt want to s pend a ton of money. Or maybe they like doing gunsmithing.