Muzzle Energy?

ZVP · November 16, 2014, 11:42 PM

How would you compare the Muzzle Energy of a 12ga "00" l9 ball load vs a 20 ga #3 ball 20 ball load?
The velocitys I found so far aew 1200-1225fps for the 12ga and 1200fps for the 20ga load. Factory velocitys.
Would you add the weights of all the Buckshot, then multiply by 2X the MV and divide by 250420? Just like solid ammo?
The energy developed by shotgun loads is awsome! I just wondered what it actually amounts to?
I love shooting these big loads for a change. I pratice HD shooying with target loads when I get a chance at the Pattern Board.
Thanks,
ZVP

JD0x0 · November 17, 2014, 02:25 AM

You are correct in that you calculate the load with the full weight of the load. Or you could calculate the muzzle energy of each pellet, using it's weight and velocity and multiply by the number of pellets

The muzzle energy from shotguns actually isn't all that impressive, IMO.
Modern .30-06 loads tend to have comparable muzzle energy to the beefiest of 12Ga loads. Also, since pellets are not aerodynamic, that energy falls off very quickly. Muzzle energy isn't extremely significant, it is only a factor in a larger equation.

If I'm not mistaken
20 pellets of #3 buck should be about 468 grains.

9 pellets of 00 buck should be about 484.2 grains.

@ 1200FPS

20ga = 1496ft-lbs
12ga = 1548ft-lbs

That's roughly the equivalent in muzzle energy to a .223 rem/5.56NATO from a 24'' barrel or 7.62x39 from a 16'' Carbine.

There are some 12Ga loads that will exceed 3000ft-lbs which is comparable to .30-06, in terms of muzzle energy, which I mentioned earlier in the post.

Dreaming100Straight · November 17, 2014, 02:41 AM

If you want to know the muzzle energy per projectile, do it per projectile. If you want to know combined muzzle energy, you need to include the weight of the wad and any buffer material if you really want to get an accurate count of all the angels dancing on the head of a pin.

B.L.E. · November 18, 2014, 10:21 PM

Quote:

Would you add the weights of all the Buckshot, then multiply by 2X the MV and divide by 250420?

No, you multiply by the square of the muzzle velocity, not twice the muzzle velocity.

You can get the weight of a lead round ball in grains by cubing it's diameter in inches, and then multiplying by 1503.

For example, a 000 buckshot ball is .35 inches in diameter.

.35 X .35 X .35 X 1503 = 65 grains.

mavracer · November 20, 2014, 07:43 AM

and the constant is 450240 not 250420

November 16, 2014, 11:42 PM	#1
ZVP Senior Member Join Date: June 20, 2009 Posts: 1,102	Muzzle Energy? How would you compare the Muzzle Energy of a 12ga "00" l9 ball load vs a 20 ga #3 ball 20 ball load? The velocitys I found so far aew 1200-1225fps for the 12ga and 1200fps for the 20ga load. Factory velocitys. Would you add the weights of all the Buckshot, then multiply by 2X the MV and divide by 250420? Just like solid ammo? The energy developed by shotgun loads is awsome! I just wondered what it actually amounts to? I love shooting these big loads for a change. I pratice HD shooying with target loads when I get a chance at the Pattern Board. Thanks, ZVP

November 17, 2014, 02:25 AM	#2
JD0x0 Senior Member Join Date: January 30, 2013 Posts: 1,037	You are correct in that you calculate the load with the full weight of the load. Or you could calculate the muzzle energy of each pellet, using it's weight and velocity and multiply by the number of pellets The muzzle energy from shotguns actually isn't all that impressive, IMO. Modern .30-06 loads tend to have comparable muzzle energy to the beefiest of 12Ga loads. Also, since pellets are not aerodynamic, that energy falls off very quickly. Muzzle energy isn't extremely significant, it is only a factor in a larger equation. If I'm not mistaken 20 pellets of #3 buck should be about 468 grains. 9 pellets of 00 buck should be about 484.2 grains. @ 1200FPS 20ga = 1496ft-lbs 12ga = 1548ft-lbs That's roughly the equivalent in muzzle energy to a .223 rem/5.56NATO from a 24'' barrel or 7.62x39 from a 16'' Carbine. There are some 12Ga loads that will exceed 3000ft-lbs which is comparable to .30-06, in terms of muzzle energy, which I mentioned earlier in the post. Last edited by JD0x0; November 17, 2014 at 02:33 AM.

November 17, 2014, 02:41 AM	#3
Dreaming100Straight Senior Member Join Date: February 3, 2013 Posts: 1,235	If you want to know the muzzle energy per projectile, do it per projectile. If you want to know combined muzzle energy, you need to include the weight of the wad and any buffer material if you really want to get an accurate count of all the angels dancing on the head of a pin.