[MarkSheppard]

Here's my rules for modelling rifles in my own OBATS:

Weapon Type HEK
Pistols 1
Bolt Action Rifles/Carbines 1
Semi Auto Rifles/Carbines 2
Full Auto Rifles/Carbines 3
7mm SMG (PPSH41) 5
9mm SMG (MP40/STEN/STERLING/MP5) 5
.45 ACP SMG (M3 and Thompson) 6
5mm Belt Fed SAW/MG (Minimi) 750 RPM 5
7mm Box Magazine SAW (BAR, BREN, RPK) 5
5mm Box Magazine SAW (M-16 Auto, RPK-74) 4
7mm Belt Fed MG (Browning/Maxim), 400-500 RPM 5
7mm Belt Fed MG (SGM), 500-700 RPM 6
7mm Belt Fed MG (FN-MAG) (650-750 to 950-1000 RPM) 6 to 8
7mm Belt Fed MG (MG-42) 1200-1300 RPM 10
12.7mm Belt Fed MG (M2HB, DShK) 450-600 RPM 10
12.7mm Belt Fed MG (NSV, M85) 700-800 RPM 11
14.5mm Belt Fed MG (KPV) 550 RPM 13

NOTES: Subtract -1 HEK if the weapon has poor reliability, IE, early M-60, early M-16A1, Chauchat, etc.