Does anyone have any idea (or know exactly)...what the "numbers" in ft. lbs. of recoil would be for a .50 Alaskan in a 7 lb. Marlin 1895SBL (18.5" barrel) vs. a 10 lb. CZ550 in .458 Lott...both firing a 500 grain bullet @ full factory load.
i.e. Grizzly Cartridge Co. loads:

50 Alaskan 500gr BCFP

Caliber: 50 ALASKAN
Bullet Wt: 500gr BCFP
Velocity: 1850fps

458 Lott 500gr TSX

Caliber: 458 LOTT
Bullet Wt: 500gr TSX
Velocity: 2225 fps

Use this calculator, you will need to know the weight of the rifle.

Recoil and Velocity Calculator

been there already...powder charges unknown, does not work without that?

The powder charge doesn't have to be exact. Look up some typical load data and plug in a few numbers.... if you're off by a few grains of powder, it just won't matter.

If you can't find load data for those cartridges, put in loads from the .458 Win. The powder capacity is a little more but it won't matter very much.

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MikeG

Muzzle Energy Calculator
I used this one and got
50 Alaskan 500gr BCFP

Caliber: 50 ALASKAN
Bullet Wt: 500gr BCFP
Velocity: 1850fps at 3801 foot lbs of energy

458 Lott 500gr TSX

Caliber: 458 LOTT
Bullet Wt: 500gr TSX
Velocity: 2225 fps at 5498 foot lbs of energy

Using this recoil calculator here
Beartooth Bullets > Ballistician's Corner > Recoil Calculator
with load data from here
Cartridge Loads - Hodgdon Reloading Data Center - data.hodgdon.com

I get the following numbers:

50 Alaskan 500gr BCFP

Caliber: 50 ALASKAN
Bullet Wt: 500gr BCFP
Velocity: 1850fps recoil energy is 54 foot pounds

458 Lott 500gr TSX

Caliber: 458 LOTT
Bullet Wt: 500gr TSX
Velocity: 2225 fps is 62 foot lbs of recoil.

These are my calculations from the sites previously mentioned and what the poster has listed in rifle weight.
I used 458 WM as an example since I couldn't find one on hodgdons data site for 458 Lott.
I also used the 500 gr. JFP listed for the Alaskan.

__________________
"People should say what they mean and mean what they say. Life is too short to be lead down the wrong path."