13.2mm HMGs

[YAN]

Hi, I have come across four types of 13.2mm Heavy Machine Guns, all based on the Hotchkiss version I think, (not counting the ones mounted in AFVs), but all have slightly different data stats;

French; Hotchkiss 13.2mm mle 1930.
Calibre: 13.2mm
Barrel length: 1.670mm
Elevation: -10° to +90°
Traverse: 360°
Weight in action: 37.5 kg
Shell weight: 0.52 g
Magazine capacity: 30 rounds
Muzzle velocity: 700 m/s
Rate of fire: 450 rpm
Max range vertical: 1.250m
Max range horizontal: 6.500m

Romanian; 1.3cm M.1931.
Calibre: 13.2mm
Barrel length: 1.670mm
Elevation: -10° to +90°
Traverse: 360°
Weight in action: 37.5 kg
Shell weight: 51 g
Magazine capacity: 30 rounds
Muzzle velocity: 700 m/s
Rate of fire: 300 rpm
Max range vertical: 2.500m
Max range horizontal: 6.500m

Greek; 13.2mm M.1930.
Calibre: 13.2mm
Length of Barrel; 1.650mm
Elevation: -10° to +90°
Traverse: 360°
Weight in Action: 37.5 kg
Shell Weight: AP 0.52 kg
Magazine capacity; 15 x Round Strip
Muzzle velocity: 800 m/s.
Rate of Fire: 450 r.p.m.
Max range vertical: 4.500m
Max range Horizontal; 6.500m

Japanese; 13.2mm Type 93.
Caliber: 13.2mm
Barrel Length: 1.300m
Elevation; -15° to 58°
Traverse: 360°
Weight in Action: 42 kg
Shell Weight: ?
Magazine: 30 rounds
Muzzle Velocity: 800 m/s
Rate of Fire: 450 rpm
Max range vertical: 4.500m
Max range Horizontal; 6.500m

Italian; Breda Modello 1931.
Caliber: 13.2mm
Barrel Length: ?
Elevation; ?
Traverse: ?
Weight in Action: 47.5 kg
Shell Weight: ?
Magazine: 20-30 rounds
Muzzle Velocity: ?
Rate of Fire: 450 rpm
Max range vertical: ?
Max range Horizontal; ?

It’s fair to say that each nation used a different type of ammo and a different type of feed (strip, belt or magazine), but things like barrel length and elevation should be similar.
Can anyone help me find out if they all should be identical or not.
Yan.