Mosin Conversion

[mauserbreed]

So... this is a little insane, and probably impossible due to the small size of the receiver, but would it be possible to convert my Mosin to .50 BMG? Sort of like the Mauser 1918 T-Gewehr...

I realize how ridiculous that may sound, but if it was possible, what modifications would be necessary? (Obviously I would need to get a new barrel machined, and the receiver obviously wouldn't fit the round.)

Also, Alternative larger bore ammunition alternatives are welcome

 

[rcmodel]

No, it is not even remotely possible.

With the Mosens rimmed cartridge feed mechanism being what it is, and it's 100 year old action strength & design to contend with?

7.62x54R seems like a pretty good caliber to leave it in to me.

It would cost you more in parts & gunsmith bills to convert it to something big & unsafe then it would cost you to go buy a completely safe & satisfactory factory rifle in .458 WinMag or .338 Laputa!

rc

 

[barnetmill]

i doubt that you could even do it as a single shot even with extensive redesigning and machine work. The backward of thrust of the 50 bmg is greater than the 7.62x54R and the receiver ring would probably not allow a barrel of sufficient thickness to be used. 50 bmg rim diameter is .804 versus a rim diameter 14.40 mm (0.567 in) for the 7.62x54R. The mausers used with an antitank cartridge IIRC was much bigger than a non-standard action. Total gun weighed 15.9 kg (35 lbs), 18.5 kg (41 lbs) loaded with the bipod. It was a single shot.
Here is a link that gives the scale: http://76.12.160.15/imageviewer/sa/...8 T-Gewehr anti-tank rifle sans bipod fitting or google this: Right side view of the Mauser 1918 T-Gewehr
The right side view shows when comparing the trigger guard that the action is massive and is not a standard 98.

 

[jaimeshawn3]

Would you consider .50-110 Winchester Express? .45-100 Sharps? There was a guy that was interested in building a buffalo rifle on a Moisin action a few months ago...
http://www.thehighroad.org/showthread.php?t=498438
Eric_F .... I wonder what he did on that project.

 

[dirtyjim]

i've seen a single shot 50-110 and a 500s&w.
to build a 50bmg mosin you would first need 3 large chunks of 4140 pre-hard, a lathe and a milling machine. then just scale up the action to bmg size.
you could even add a rim to the bmg case just to keep the look.

several months and hundreds of machine hours later you just might have a working action.

50 alaskan would be doable

 

[Gunnerboy]

^ what he said but that would be the coolest mosin nagant ever especially if you could scale up everything stock bayonet sights etc..

 

[Cosmoline]

IIRC there was a scaled-up Mauser 98 used in an anti-tank capacity. The same could be done with the Mosin design, but would require an advanced knowledge of gun making. You'd have to build it from scratch, and could not use old receivers.

 

[Clark]

The 50BMG will not fit in the bolt bore, so the barrel will have to be unscrewed for each shot.

I have often thought of converting a Swedish Mauser to 50BMG that would have the same problem.

The point would be to work up until the lugs or lug abutments moved and headspaced increased. This would be a way of measuring the strength of the action.

I have converted the Mosin Nagant to 45/70 and 30-30.

 

[NCsmitty]

The sensible approach to converting a Mosin, is to utilize the original 54R case necked down or necked up from 6.5mm through 9.3mm and fitted with a new barrel. Reamers are available for these conversions, and the magazines need little or no attention with the change.

It's hard to beat the 7.62x54R for all around use, with performance on par with the 308/30'06, and surplus ammo under $.20 a round, it's a bargain.


NCsmitty