Muzzle energy of shotgun loads

[Charles Lawrence]

How do you calculate the relative muzzle energy (or felt recoil) of various shotgun loads using load weight and muzzle velocity?

[Kosh75287]

(projectile weight in grains x muzzle velocity (f/s) x muzzle velocity (f/s)) divided by 450240

[shortlegs]

Look up recoil calculator on line.

[Kosh75287]

Look up recoil calculator on line.

Sorry, I didn't see the f(or felt recoil) part.

[shortlegs]

That would be the recoil energy. ShootersCalculator.com

[barnetmill]

Is the wadding a significant part of the calculation? As to what is 'felt', the weight of the shotgun should be included in order to calculate the velocity of the recoil that is needed.

[megasupermagnum]

Is the wadding a significant part of the calculation? As to what is 'felt', the weight of the shotgun should be included in order to calculate the velocity of the recoil that is needed.

No. Even the heaviest wads are likely to be a steel shot wad. They are like 40 grains, some more, some less. 40 grain wad is nothing compared to 492 grains of shot.

[Milsurp Junkie]

No. Even the heaviest wads are likely to be a steel shot wad. They are like 40 grains, some more, some less. 40 grain wad is nothing compared to 492 grains of shot.

Well, 8% or so.:-)

[Geezer in NH]

Muzzle energy = 1

Recoil energy = 2

Which do you want?

[W.R.Buchanan]

The recoil energy is what it is. The actual relative power of the load is best expressed by TKO IMHO> TKO or Taylor Knockout Value is arrived at by using the following formula.

Diameter of Bullet/Slug x Weight in Grains x Velocity / 7000. This will yield a 2 or 3 digit number than can then be compared to other cartridges.

Example: a 12 ga. 1 oz. Slug at 1600 fps= TKO 72.9,,, Compared to a .458 Win Mag 500 gr Bullet at 2150 fps .458 x 500 x 2150= TKO 70.3

So a 12 ga Shotgun with a high base slug is very close to a .458 Win Mag. But the difference is how the energy is transferred to the target. The Slug due to it's larger diameter, Transfers most of its energy instantaneously to the target. The Frontal Area of the Rifle Bullet is only 1/3 of the Frontal Area of the Slug (.164 Sq in versus .418 Sq in.) so it becomes obvious which one will transfer its energy more efficiently. (VW vs Bus analogy) The rifle bullet will penetrate further than the slug which in some cases is more desirable or it will go all the way thru the target and end up expending its energy into the ground beyond. Application determines which is better for you.

The recoil energy of this is the back side of the equation. Brenneke makes a 1 1/2 oz. Slug that runs 1600 fps! It is suitable for hunting T Rex! The TKO on that load is 109! And touching one off in a 7 lb. shotgun would be a life altering experience !

Randy