M D N

8x50mmR Lebel came in three major flavors.

 

I mentioned that GURPS gave us stats for what appeared to be the Lebel in Balle M, Balle D and Balle N, recently. 

To repeat:

Balle M (1886) is from Adventure Guns with 6d+2 pi, 800/3,300.
Balle D (1898) is from Pulp Guns with 6d+2 pi, 1,000/4,200.
Balle N (1932) is from High Tech with 6d pi, 900/3,900. 

Gun Stats gives:

Balle M (232 gr, 1.2" long bullet at 2,060 fps) 6d+1 pi, 920/3,900
Balle D (198 gr, 1.54" long bullet at 2,300 fps) 6d+2 pi, 1,080/4,500 OR (198 gr, 1.54" long bullet at 2,400 fps) 7d-1 pi, 1,120/4,700
Balle N (231 gr, 1.54" long bullet at 2,200 fps) 7d-1 pi, 1,200/5,000 OR (231 gr, 1.54" long bullet at 2,300 fps) 7d pi, 1,260/5,300

Assuming that the Balle N bullet is identical dimensions as the Balle D, just lead core instead of solid brass.

I've found contradictory sources for the muzzle velocities for all three rounds.