Comparative Recoil
.22 Pistol	1.1 J	.22 Rifle	< 1 J
.25 acp pistol	1.5 J	.223 rifle (M-16)	5.0 J
9mm Pistol	5.4 J	.308 Rifle (M-14)	18 J
.45 acp pistol	7.9 J	12 gauge Shotgun	30 J
.44 magnum	20 J	.458 Elephant Gun	75 J

English to Metric conversion Kinetic and Free Recoil Energy Bullet Weight (gns) Projectile Mass (g) Import English into SI units. Bullet Velocity (fps) Projectile Velocity (m/s) Calculate KE and RE Propellent Weight (gns) Propellant Mass (g) Kinetic Energy (J) Weapon Weight (lbs) Weapon Mass (kg) Recoil Energy (J)

Further Notes on Recoil

It should be noted that free recoil energy is really only a comparitive look at at recoil. Felt recoil is highly subjective and is affected by a large number of factors. The shape and area of the weapon/firer interface (butt) plays a large role. A larger butt area means less force is applied per cubic centimeter of contact area. Felt recoil can also be reduced through the use of recoil absorbing devices like rubber butt pads, recoil absorbing springs and muzzle brakes. There are also techniques of recoil reduction that use counter masses to absorb recoil energy like open bolt weapons and so called 'soft recoil' weapons, where a large percentage of the weapon is accelerated in opposition to recoil force, nullifying a significant part of the recoil generated.