I understand a foot pound is the kenetic energy required to lift one pound one foot. A .30-06 has a rating of 2,829 foot-pounds of energy at the muzzle. I can't believe the .30-06 cartridge could lift a ton and a half one foot off the ground. So, what do these ratings really mean? How do the manufactures compute there findings?
2007-12-10 02:20:44 · 4 answers · asked by jack-copeland@sbcglobal.net 4 in Science & Mathematics ➔ Physics
It is a measure of the energy in the bullet. A foot-pound will lift one pound a distance of 1 foot--in one second.
So, lets say you have a bullet that weighs 1/100 of a pound. If it has enough energy to move 100 feet in 1 second, it has 1 foot pound; if it moves 200 feet in 1 second, it has 2 foot pounds, if it moves 1000 feet in one second, it has 10 foot pounds.
If your bullet weighs 1/50 of a pound, and moves 100 feet in 1 second, thats 2 foot pounds.
See the pattern?
2007-12-10 02:29:30 · answer #1 · answered by Anonymous · 1⤊ 1⤋
The previous answers are very good as far as the general physics of foot-pound ratings go.
You can also consider that the higher the foot pound ratings are of a bullet will also relate to velocity and knock down power.
Say a lighter bullet, a .22 for instance may enter the body but not leave it. But shoot a body with with a .30-06 it will enter the size of the .30-06 and leave a massive hole in the back of the body. Foot per pound rating in action.
2007-12-11 18:41:32 · answer #2 · answered by ♥♥The Queen Has Spoken♥♥ 7 · 0⤊ 0⤋
Foot-pounds is a measure of the work that the bullet is capable of. A 30-06 cartridge can't lift a ton and a half off of the ground like you say because there's no way to efficiently couple the energy in the round to the thing you're trying to move. But if you could take the charge (or potential energy) of the smokeless powder that propelled the bullet and place it correctly under your load then, yeah, it could move it one foot.
2007-12-10 11:30:16 · answer #3 · answered by the_meadowlander 4 · 1⤊ 0⤋
A foot-pound is a unit of work or change in kinetic energy in the English system of measurements.
I am hypothisizing here but I would imagine gun makers would just look at the mass and velocity of the bullet and would then know how much work would be required to reduce the velocity to zero relative to the gun.
2007-12-10 11:34:53 · answer #4 · answered by Anonymous · 0⤊ 0⤋