Doubts about allies

[Engineering0110]

We know that the Allied West Front is not the protagonist of the game.
And the machine gun of the tank in the game needs 800M to attack, not 1000M. Why is the range different from M2HB?
Why do tanks and anti-aircraft vehicles have different ranges of the same machine gun?
Many of the aircraft's weapons can be attacked at 1000-1300M, but the anti-aircraft weapons on the roof of the M4 tank have a range of only 800M.
Why do the French have M4A3 76 W?
Americans don't.

[[EUG]MadMat]

Why do the French have M4A3 76 W?
Americans don't.

Because it so happened IRL.
The Americans got 76mm Shermans way before the French, in the form of M4A1(76), but the French were the first (and only before the end of the Normandy campaign) to get the new M4A3(76).
They were delivered as replacement for the M4A2 lost in the 2e DB's earliest engagements.

[Grabbed_by_the_Spets]

nd the machine gun of the tank in the game needs 800M to attack, not 1000M. Why is the range different from M2HB?

M2's are .50's(~12mm) as opposed to most other machineguns which are .30's(~7-8mm). .50's retain more energy, a flatter trajectory and a higher velocity, making them more deadly at longer ranges than .30's. The DShKA is a .50 and has 1000mm range too.

Why do tanks and anti-aircraft vehicles have different ranges of the same machine gun?
Many of the aircraft's weapons can be attacked at 1000-1300M, but the anti-aircraft weapons on the roof of the M4 tank have a range of only 800M.

Machine guns used for AA usually have got a mount on it specifically to allow maneuver against fast flying AA, including a centralized seat with AA optics, 360 rotation and a firing arch of almost 90' which allows for tracing planes over longer and trickier situations.