ej, according to Steve Ricciardelli, (http://stevespages.com/page8a.htm - W-748 From 41.6 grains to 48.8 grains) 48.8 grain of WW 748 isa max load with the 175-grain Sierra flatbase spitzer bullet. I see no reason why you cannot start with 45 grains and develop a load for his rifle, PROVIDED he has had it checked by a competent gunsmith who says it is safe to shoot with 7.92X57JS military ammo....

That Sierra 175-grainer at 2400 FPS will certainly kill elk, but if it were I developing an elk load for the 8X57mm (an "S" -.323" bore), I'd use either the 200-grain Nosler Partition or 200-grain Nosler Accubond bullet at 2400 FPS, which you can do with IMR 4350 or RE 19.....