Home Forums Hunting & Shooting Hunting Rifles Bullet Energy.......AGAIN!!!!!!!!

More energy won't make the spine more severed, the brain more mush, or the lungs/heart more perforated...

If 100 or so elk were shot equally, but at varying distances with (say) a 257 Roberts and 100 gr Partitions,and an equal number shot with a 300 Weatherby and 180's(satisfying the OP's requirement for different calibers in his question),I wouldn't be surprised to see more trauma,damage to bone,more extensive wound channels,and generally more satisfactory results and (maybe)quicker kills from the 300.This kinda makes sense.

I say this because I've compared the damage to elk (not 100 of them made with 30 caliber and 25 caliber bullets....but I don't think it was "energy" that made the difference.I think it was the greater bullet mass,and expanded frontal area,and deeper penetration of the 30 caliber bullet that inflicted more damage.If the 30 caliber bullet were slowed down,and the 100 gr bullet speeded up,so that paper energy were the "same",I'd expect to see pretty much the same results.

Bullet weight and caliber are "constants";velocity and energy are not,energy being nothing more than a calculation that fails to take into account bullet construction and the capacity of the bullet to inflict "damage" in expanded form.

I'd also expect the lines to get a bit fuzzier as bullet weight and caliber got a bit closer,even if energy figures were different or the same for each.



In a less extreme example,(maybe this is what the OP meant) where a 270 bullet gets outpaced by a 7mm bullet by 200-300 fpe of "paper" energy.....no, I don't believe there is any difference at all if penetration and expansion are at all the same.

Energy numbers are just fodder for internet chitter/chatter.

As has already been said, not necessarily. 'Energy' (more specifically kinetic energy) is simply a calculated quantity, which is a function of velocity and mass. In general it is an incredibly useful value, however, not so much with terminal ballistics (i.e. inflicting damage on the target). For one thing, velocity is squared in the formula for KE, which can tend to 'distort' the relative importance of mass and velocity when it comes to analysis of terminal ballistics. Then there is the well documented fact that only a relatively small amount of energy (compared to the total for 'typical' centrefire rifle cartridges) is required to produce a lethal wound channel. Anything over and above that isn't going to be very meaningful in terms of 'increased lethality'. There is some more required to 'deform' (i.e. open) the bullet. However, that can usually be considered in terms of a minimum terminal velocity, rather than worrying about energy.

As has also been mentioned in previous posts, 'opening' of the bullet isn't even a required event in order for a lethal wound to be inflicted. A .30 cal 'solid', at 'normal' centrefire rifle cartridge velocities has plenty of damage inflicting potential. Although I wouldn't say that energy is entirely meaningless, it is probably more useful to consider simply the 'base' figures of velocity and mass rather than worrying about derived values such as momentum or energy.

Of course, as has also been mentioned, location is the single most important consideration. Yet that usually isn't considered when getting into more theoretical analysis (when homogeneous media such as ballistic gell are often used) of terminal ballistics. Once you've made an assumption regarding 'appropriate' location, a direct comparison of mass, velocity, bullet (construction etc.) caliber will probably tell you all you need to know in terms of comparison. Calculated quantities such as 'energy' don't really add much.

Bob,your first paragraph makes alot of sense.
Your last paragraph is what i'm thinking about.

I'm between buying a 7mm08 & a 308. The bullet wieghts and bullets i was comparing were 140g for the 708 and 165g for the 308...both bullets were Federal Premium Trophy Bonded.

I agree with you guys that you can't look @ energy as the only determining factor for killing.Nothing will ever replace shot placement.

Gravestone: You will kill nicely with either one...and there are lots of good reasons for choosing a 308.....but personally I'm a 7/08 fan myself,and it would be my choice in a short action rifle for most of the hunting and shooting that I do.JMHO.

Big +1

That's nearly identical to what I would write if I weren't too lazy to type it all out