Some small homerule from a person interested in firearms. Weapons are listed without magazines or ammo loaded (empty), ammo is listed separately.
1) Autopistol
Weight empty - 1,1 kg
Fully loaded magazine (20 rds) - 0,4 kg
Referance:Beretta 93R
2) Autogun
Weight empty - 3.1 kg
Fully loaded magazine (30 rds) - 0.75 kg
Referance: Kalashnikov AKM
3) Lasgun
Weight empty - 3.5 kg
Power cell - 0.5 kg
Referance: Colt M16A2
4) Heavy stubber
Weight empty - 12 kg
200 rds belt and its box - 6,5 kg
Referance: FN MAG
5) Bolter (boltgun)
Weight empty - 5,5 kg
Magazine (24 rds) - 1.5 kg
Referance: XM-25 grenade launcher
6) Heavy bolter
Weight empty - 16 kg
Ammo box (60 rds) - 25 kg
Referance: AGS-30 greande launcher
7) Meltagun
Weight empty - 6 kg
Fuel canister - 2 kg
8) Plasma gun
Weight empty - 5 kg
Fuel cell - 1,2 kg