Swedish Mauser for 444 Marlin project?

[Ranch Dog]

Any opinion on this Swedish Mauser as a candidate for chamber boring to 444 Marlin?

Swedish Mauser chambered for .410

I sent the seller a message to see if it is a 2 1/2" chamber. That would work but 3" wouldn't.

[Chickenthief]

Some math are in place:

Area = radius x radius x Pi
6.5x55 bottom area (ø=.48") = .24" x .24" x 3.1415 = 0.181squi
T4 bottom area (ø=.514") = .257" x .257" x 3.1415 = .207squi
This is important because of the max force applied to the bolt.
6.5x55: 55114psi x .181 = 9975 pounds of force on the bolt.
T4: 51488psi x .207 = 10658 pounds of force on the bolt.

So T4 pressures would need to be lowered to 48200psi max.
The German '96 Mauser actions are older and in general of weaker steel than the Swedish (Husqvarna) actions.





On a side note, do you know why the 6.5x55 has a lower max pressure than all other Mausers of the time?

Because the Danes has a military pact with Napoleon in the early 1800's!

Here's the thing:
The UK had a pact with Russia and Napoleon invaded russia.
We had a big fleet and the UK was scared of it so they invaded us and sank the Danish fleet (and terror bombed Copenhagen).
At the time we had Norway but it was lost as war damage when we surrendered to the UK.
Norway wich had been under 300+ years of Danish government had next to no military so they formed an alliance with Sweden.
The Remington 1867 in 12.7x44R was their first common caliber. The 8x58RD was next as an interim measure until good smokeless was produced.
Then came the 6.5x55, the Swedes opted for a Mauser but the Norwegans wanted a Krag-Jørgensen of their own making wich has a much weaker action and needed a lower pressure.

[Ranch Dog]

Thanks for all the info including the history behind the rifle design. The 48.2 KPSI max is quite do able for me personally as it is pretty tough to get a cast bullet to survive above 48.0 KPSI. Most of my shooting is done at 42.0 KPSI.

[akuser47]

I'm betting some of the low pressure s on old military cartridge was do to the propellant used like stick cordit. But I'm not versed in cordit verses smokeless in those eras. But sure someone has done more info on comparisons of them.