This damage table at gamefaqs may be useful, assuming handgun is power 1:
http://www.gamefaqs.com/arcade/917559-metal-slug-5/faqs/32498
SLUG ABILITIES
Slide Enlarged Machinegun Machinegun Bomb Self Stab
Normal Yes - 200 4 10 - 3
BIG - Yes 200 4 10 - 3
SVW - - Infinite 5 20 40 -
SVWe - - Infinite 5 20 40 9
Aircraft - - Infinite 5 20 40 -
Submarine - - Infinite 3 20 40 -
Slugmobile - - Infinite 5 20 - -
Spider - - Infinite 2x5 20, 20 40 -
WEAPON UPGRADES
Insignia Name Ammo Depletion Power
S Shotgun 30 1 20
2H Dual Machinegun 300 8 8 per 8
H Heavy Machinegun 200 4 4 per 4
G Super Grenade 20 1 10
C Enemy Chaser 40 1 3
L Laser 200 4 8 per 4
D Drop shot 30 1 3
R Rocket Launcher 30 1 3
I Iron Lizard 30 1 3
ENEMIES
Class Name Energy
Tank Cannon tank 70
3-Burst tank 50
Machinegun tank 40
Missile tank 40
Green Cannon tank 25
Bowling tank 20
Vehicles Red black hawk 80
Chopper (Red tint, Red) 28
Submarine 10
Airplane 6
Missile bike 6
Hover 5
River hog 4
Motorcycle 3
Various Bowling truck 50
Enemy delivery truck 50
Truck 32
Pillar (4 stages) 9, 9, 9, 9
Larva nest 20
Big ICBM 20
Lift truck 16
ICBM 10
Sea mine 8
Squid 7
Electric Jelly fish 4
Big jelly fish 3
Jelly fish 3
Elevator bots 3
Objects Ruins 30
Barricade 30
"Keep out" door 28
SVW crate 20
Sniper bushes 16
Grunt's shield 15
Droid head armour 15
Sandbag pile 15
5x sandbags 15
Generator 15
Big metal crate 13
Sandbag trench 10
Toxic's barrel base 2, 4, 4
Sniper crate 8
Toxic's barrel bottom 5
Small metal crate 5
Bushes 4