Hm, I did some more work on tank MG loadouts using the same formula, but slightly modified
Official Ammo Load	6000	rounds (based on M4 Sherman official loadout)
+50% Ammo Load (Simulates people carrying extra ammo)	9000	rounds
Weapons of Vehicle using Same Calibre (tank MGs)	3	
Ammo Load Per Weapon	3000	rounds
Rate of Fire (effective) for the Weapon	300	RPM
Rate of Fire in Rounds Per Second for the Weapon	5	RPS
Ammunition Expended per Action	75	rounds
Shots for Weapon	120	shots
So yeah, the tank MG loadouts are actually quite accurate!  
