AL Miller in his publication in The Rifle - Jan.-Feb. 1971 gives the original data given for the 5,6X61R vom Hofe Super Express is 46,935 psi & a muzzle velocity of 3,280 fps(ft/s). I may inch up towards 45 grains of VV N 160 but I am only say 100 ft/s on the top side from the guesstimate......

Hochachtungsvoll,

Raimey
rse