how do you figure out which bullet is more powerful?

[horatioo]

Is it a function of weight, fps and energy? I have been researching getting a gun and dont know which of some of the various cartgridges have more power. I can look up the weight, speed and energy on wikipedia.

Also what is 'energy'?


Bullet weight/type Velocity Energy
123 gr (8.0 g) Spitzer 710 m/s (2,300 ft/s) 2,010 J (1,480 ft·lbf)

Thanks

 

[Jon1911]

Ballistic Energy is a complicated calculation. I don't know that there's an easy answer.

 

[Maromero]

E=MC2

 

[Red Tornado]

As a general rule, the higher the muzzle energy, the more powerful the cartridge. There is endless debate regarding bullet mass, diameter, velocity, meplat size, knock down power, ad infinitum.

However, a .22 lr at around 110 ft/lbs is definitely less powerful than 9mm somewhere around 350 ft/lbs which is definitely less powerful than a .223 around 1200 ft/lbs which is definitely less powerful than a 30-06 around 2500 ft/lbs which is definitely less powerful and a 50BMG at bajillion ft/lbs. (I can't remember the .50 even vaguely, but I think it's north of 10,000 ft lbs.)

Everything pretty much fits in there somewhere. You can find a 9mm and .45 acp that have the same energy, though, hence the endless 9 vs 45 debates on every gun board in the universe.

Oh, BTW, I believe your energy = mass x velocity(squared)
RT

 

[roy reali]

Higher Velocity?

Energy doesn;t kill. Organ and tissue destruction does. A .22-250 devolps more muzzle energy then any "old-school" .45-70 load. However, which would you prefer to have if bear was charging at you?

 

[Double J]

A quik way to figure any bullet's energy:

Velocity in feet per second x velocity in feet per second
x bullet weight in grains
Then divide this by 450,000

This will give you a figure to use as a guide when comparing to other loads. It is only a guide as there are other considerations such as caliber, bullet design, trajectory requirement, overall accuracy, recoil, etc.
It boils down to you deciding what application you intend to use a particular bullet. You'll notice there may be several bullets for a given caliber. Even though the energy levels may be similar, they may be designed for different situations.

 

[44 AMP]

ME is a rough rule of thumb

for comparison only. There are a huge number of other factors involved. Light fast bullets can have the same energy as slow heavy ones. But their effect on the target can be radically different.

Size of the bullet (frontal area, as well as total weight) seems to be a major factor. The reason many bullets are made to expand is to increase the frontal area, and thereby their effect in tissue.

Speed is a factor, but not a linear one. Once certain velocity levels are crossed, the bullets effect in tissue changes, becoming more disruptive (if only temporarily) in any soft tissue.

I liked the comparison between the .22-250 and the .45-70. Both can have similar amounts of energy (a .22cal 50gr @ 3800fps is 1600ft/lbs, and a .45 cal 405gr @ 1350fps is 1640ft/lbs), but their effect on animals is radically different. While the energy is virtually the same, the size, weight, speed, and bullet construction are not.

While not availabe to those without guns, recoil is another rough (really rough) measure of a cartridge's power. Power, not calculated energy. But shooting different guns, and noting the different level of "kick" will give you a really rough idea. Many, many other factors are in play here, but you get the idea (I hope).

 

[Dave R]

Here's an accurate answer that sorta says nothing at all.

The total amount of energy in the round is a function of how much, and what kind, of powder it burns. More powder generally equals more energy.

The bullet weight and construction determines how that energy is transferred to the target.