Axle E. on 0.318" vs 0.323":
"Apparently the changeover was completed 1926. Jon Speed's book "Original Oberndorf Sporting Rifles", page 274, shows a table of cartridge dimensions agreed upon July 23, 1926 by the German arms and ammo manufacturers association. It shows new//old designations: 8x57IR // M88/8 mit Rand or M88B, 8x57I // M88N, 8x51 // M88/8 kurz or H, 8x57IS // M88/8S.
The German M1888 cartridge was loaded with a .318" 14.7gramm = 227grs (roughly 15gramm)round nose bullet. This was the standard/only hunting load up to WW1. The military S cartridge used a .323" 10g = 154gr pointed bullet that never became popular as a sporting load. In WW1 the German army changed to the sS = heavy pointed bullet for machine gun use, bullet weight 12,7g =196gr. This became the standard weight for both the I and S bores close to WW2. Up until after WW2 the I = .318" bullet was regarded as the sporting type, while the S-bore was the "military" one, used on Sporting rifles mostly for the "Magnum" loads to relieve pressures. Only the 1940 proof law introduced min-max dimensions and the strict differentiating between I and S bores. So take any rifle proofed for a 15g bullet to be an I bore. Also, any other commercial pre-WW2 8mm barrel, except you prooved otherwise by slugging the bore and making a chamber cast."
15 gramme projectile:
"The German M1888 cartridge was loaded with a .318" 14.7gramm = 227grs (roughly 15gramm)round nose bullet."
http://www.doublegunshop.com/forums/ubbthreads.php?ubb=showflat&Number=442941http://www.doublegunshop.com/forums/ubbt...true#Post277508Cheers,
Raimey
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