The MG 42 was the primary German machine gun of WWII. It is called the "Hitler's Buzz Saw" by Allied troops, it is so effective that the American M-60 machine gun was based on it. It's rate of fire, between 1,200 and 1,500 rounds per minute, gave it its distinctive sound and is among the highest of any gun ever made. Later models actually reduced the rate of fire to conserve ammo and reduce the wear on the gun. Very deadly in good hands and will pin down your troops for a pretty long time.
MG 42 is basically the Browning M1919 with longer range, better firerate but without the target switching ability.