The MP40 was the weapon of choice for the German tanker, stormtrooper, sergeant and officer during the Second Weltkrieg. Its low rate of fire (hence the characteristic "plap-plap-plap" sound report) allowed it to put down controllable, if slower automatic fire downrange.
EFFECT:
This weapon may not fire more than half of its magazine in Auto bursts within a single action, but its hit roll penalty will not increase with each successive shot fired.