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Hueco
January 9, 2000, 01:11 PM
From what you guys have told me, and from what I have read, this is what I believe to know about "killing power" of idfferent calibres and weights:

A light, fast bullet will not penetrate as well as a heavier bullet at a lower speed. The light, fast bullet will over-expand and thus not penetrate -- it will make a big, short channel. The heavy, slow bullet will make a narrow (smaller diameter), but long wound channel and impart more damage.

Is this correct?


Hueco

Rich Lucibella
January 9, 2000, 02:48 PM
Sometimes. ;)
Sorry for the facetious answer, but few could say more than that. All things being equal, you've stated a fair but very broad generalization....for handguns. At rifle speeds lots of other factors come into play.

The Devil's in the myriad exceptions. One way to level the playing field is thru proper shot placement(s)....that done, you can check the type of bullet when you get home. :)
Rich

Hueco
January 9, 2000, 03:31 PM
Hey there. Yeah, generally is really all I needed confirmation on. I do realize that there are a lot of other variables that can affect this subject. Thanks!

Hueco

James K
January 9, 2000, 05:42 PM
Hi, Hueco,

The world's armed forces, whose business is killing people, have gone in 200 years from a slow bullet of about 70+ caliber, to a faster bullet of 55+ caliber, to a faster bullet of 30+ caliber, to a faster bullet of 20+ caliber. So the theory that big slow bullets will kill about as well as small fast bullets seems to hold some water. (I know that the change to 5.56 by the U.S. was due to controllability in full auto fire, not especially for better killing power, but the change would not have been made if the latter were not adequate.)

Jim

Art Eatman
January 9, 2000, 06:26 PM
I'd qualify your statement by saying, don't use "over-expand". Just "expand" will do.

The light, fast bullet will not penetrate "as deeply" as the heavy slow bullet, but this is due to its design. A full-metal-jacketed bullet of 30-caliber will penetrate as deeply if not deeper than a .45-70. An expanding bullet will not.

Design and purpose must always be considered. A light, fast bullet will work well on deer and elk, but not worth a hoot on an African buffalo. The latter has far thicker skin and much heavier bones. However, most guns used for African buffalo use a large-bore, heavy bullet moving fairly FAST--which is why the guns are usually fairly heavy yet still have notable recoil.

You're on the right track, but there's still a way to go.

:), Art

Pierre
January 14, 2000, 04:09 PM
Just a note on small caliber fast traveling projectiles.........their "killing power" is based on the effect of "hydrostatic shock". Just as ultimately deadly as the larger, slower traveling projectiles.

Alan B
January 14, 2000, 05:19 PM
Also if you look through the some military Manuals in their discussion of rifles, some time in the late 60s they change from talking about killing potential to a rifles wounding potential. Which if I remember right was the Japanese philosophy during WWII. Since it takes 2 - 4 healthy soldiers to remove and care for each wounded soldier it was felt wounding the enemy depleted enemy forces faster than killing did. Nice theory, until you go up against an enemy who doesn’t care a wit about the wounded.
There is a limit to how much velocity will help a smaller bullet, A 7.62 NATO 147 gr FMJ retains more KE at 500 meters than the 55gr FMJ 5.56 has when leaving the end of the gun. Without getting out my physics book, some of the earlier changes in bullets traded weight for speed but retained the same relative KE for a bullet that had better flight characteristics. The Army adopted the M1911 not because of its killing potential but because if the 230 gr slow slug hit you anywhere, you went down, It was big enough yet slow enough that when it hit, it would transfer all it KE in to the target. It proved to be a very good combination of the two (Blame the Moro warriors the 38 pistol rounds would punch holes in them but not take them down.) Too small and too fast is just as bad as too big and too slow it’s a double edged sword and can cut both ways. There is a happy medium in the center. For the 5.56 rounds to have the same KE as a 7.62 they would have to be a lot faster (like about 1.5 times, its an exponential relationship if you want Ill look it up) but at that speed they would probably punch through the target and not impart much of their KE as damage to the target. The best combinations are were you have as high KE as possible which is totally transferred to the target on impact but does not allow the bullet to exit the target. (How’s that for an answer right out of a calculus based physics book)