Can someone please give me the formula to calculate delivered energy? For instance, a 230gr bullet travelling at 850 fps delivers how much energy to a target at 25 yards?
How much vaiation in ft/lbs does barrel length give.
For instance, the same scenario above using a 5" barrel, and a 3" barrel.
2007-11-03 09:49:00 · 2 answers · asked by Anonymous in Sports ➔ Outdoor Recreation ➔ Hunting
To calculate the kinetic energy of a bullet, multiply the weight of the bullet in grains times the velocity in ft. per second squared and divide this number by 450400. The number that you get is the energy of that bullet at that velocity in ft. pounds.
In the case that you gave, you multiply 230 by 850 squared to get 113,390,000. Then you divide this number by 450400 to get 251.8 ft. pounds of energy. How fast the bullet is going at 25 yards will depend on the ballistic coefficient of the bullet, the temperature and the density of the air. This velocity will determine the ft. pounds at 25 yards. You can safely assume that the kinetic energy at 25 yards won't be very much below the kinetic energy at the muzzle, though.
A very good book that will explain this to you is "Understanding Firearm Ballistics" by Robert A. Rinker.
If the powder that you have in the cartridges is completely burned in 3 inches, the extra 2 inches will not make that much difference. However, if the powder is slow burning enough that you have unburned powder exiting the muzzle of the 3 inch barrel, then the extra 2 inches will make a difference. How much difference depends on how much of the powder is burned in 3 inches and how much is burned in 5 inches. This is a function of the particular powder and there is no definative answer without knowing what powder you are using and what it's burning rate is.
2007-11-03 15:45:22 · answer #1 · answered by Anonymous · 3⤊ 0⤋
Muzzle Energy Calculator
2016-09-28 01:04:51 · answer #2 · answered by ? 4 · 0⤊ 0⤋
CIH is right in that there are a lot of variables,
but I think you will find that the difference between
a 3" and 5" barrel with any given load will be
substantial.
As to your 230Gr. Bullet at 850fps.:
You are talking .45 ACP ballisitcs and the
muzzle energy will be about 350 Ft. Lb.s.
(I doubt you will get the velocity out of a 3" Bbl.
with a safe load.)
2007-11-03 17:55:29 · answer #3 · answered by Irv S 7 · 1⤊ 0⤋
The Ammo Guide ballistic calculator can figure out most things, other than the mass and speed to muzzle velocity.
That's here: http://www.ammoguide.com/cgi-bin/bcalculator.cgi
There's another calculator for speed and weight into velocity, as well as other factors, that's here: http://handloads.com/calc/quick.asp
2007-11-03 10:27:40 · answer #4 · answered by fishtrembleatmyname 5 · 1⤊ 0⤋
calculating ftlbs energy bullet
2016-01-23 22:56:57 · answer #5 · answered by ? 4 · 0⤊ 0⤋
Bullet Energy Calculator
2016-06-25 21:01:44 · answer #6 · answered by ? 4 · 0⤊ 0⤋
It's a simple formula:
energy=weightXvelocityXvelocity
or E=MC^2, where E is energy, M is mass, and C is velocity. It's the mass of the bullet times the velocity squared.
2007-11-03 10:15:36 · answer #7 · answered by Anonymous · 1⤊ 7⤋