9 X 77 HECKLER & KOCH XPL

Research notes

During the late 80’s, the German firm of Heckler & Koch started work on a long-range sniper rifle/cartridge. The design was based on a 9mm bullet of 22g (340 grain) and a muzzle velocity of 1,050 m/s (3,400 fps) from a semi-auto rifle. Initial work was done by Lapua from computer generated models based on a 72mm case but did not yield the desired ballistics and the case length was increased to 77mm with cartridges manufactured by MEN. Test results also did not yield the desired ballistics from the original design criteria and accuracy beyond 600m was also poor. Further development was done leading to the 9x85mm H&K.

Smith P - Variations of Military Experimental Calibers