Stainless steel booster cups for British Vickers/Maxim guns. These are in a 'blank' form. The only
operation remaining is to thread the back of the cup with the appropriate thread to fit the barrel
muzzle. This is done when the order is placed. The .303 British barrel uses 5/8-20 threads.
We have modified German 8 x 57 and Russian 7.62 x 54R barrels to fit in the Vickers/Maxim guns thus
permitting use of more readily available ammunition. Modifications include reducing the diameter of
the trunion bosses, reducing the size of the rectangular breech block and machining and knurling a
packing groove in the proper location to seal the water jacket of the BV/M. In the case of the Russian
barrels, the muzzle end is turned to match the German barrel. These booster cups are then threaded
M15 x 1.25 to fit the metric threads on the muzzles of these barrels.