[OldManEtwon]

Not Completely sure about these but these are just a guess

Rifles
Timberwolf = .308 rifle
Grizzly = .50 Rifle
Mata = .22 long?
Sabertooth = .45 long? maybe .223 long
Snay = .806?

Carbines
Peacemaker = .22 long?
Honeybadger = .22 long?

Assault Rifles
Eaglefire = .556
Maplestrike = .556
Zube = .762

These are just some of the guns I could think of and their possible caliber