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What are the thoughts concerning downrange momentum (mass x velocity) compared to downrange energy (1/2 Mass x energy x energy) as an indicator of killing power? Now rembember, both Keith and Taylor didn't believe that energy was the best measurement. Also remember that the killing power of some cartriges is not well explained from their somewhat dismal downrange energy alone.

Wayne

Mathematics is an overrated consideration in klling power.

Just yesterday I read a thread on the 6.5 X 55 whereby the little 100 gn Barnes X out penetrated just about everything else, regardless of weight or design in that caliber.

I myself have killed 200 pound varmints at 600 yards with complete penetration, using 53 grain XBT's in a humble .223 Remington.

Killing power on paper means little compared to field experience, which can surprise all, based on averaging out results.

Save your energy for reloading cartridges.

AGW

Exactly.......Math means little in the field.........

Engineers must quantify all that they can or they wouldn't be engineers. Energy is quantification based upon observable and repeatable actions which allow people to compare various bullets, cartridges, rifles, etc. Momentum will work also. So will candlesticks, mushrooms, ice or just about anything that people will agree means the same thing to all of them.

Energy is used because most folks understand that energy is energy and not something magical or mysterious. If you don't like energy, for whatever reason. then don't use it.

I don't have any particular hang up about using energy because I am an engineer and understand that 1 inch is 25.4mm is 2.54cm.

And how does energy relate to the wounding process?.......

I really have no idea.

However, I would postulate that bullet design (soft point vs flat point, heavy wall vs light wall jacket, etc) would probably contribute more to wound damage that energy or momentum, especially when comparing two differently constructed bullets with comparable energy and momentum figures.

Energy and momemtum are just two ways of providing information regarding observed data. I think that high energy bullets with low momentum would inflict serious shallow wounds and low energy bullets with high momentum would give greater penetration.

But again, its just a measurment system that most folks can agree upon and work with.

Good answer...........

I think you meant to say "downrange energy = 1/2 mass x velocity x velocity.

Here, here! My high school and college math grades prove that math means little! ........or that I'm not good at math!

Expat

I used to believe all that fancy stuff about KO's and FPE and Momentum. There's another theory out there I'm believin' in more and more each day....pictures being worth a thousand words they say....



Another thought, not my own however. Well, I think this fella knows what he's talking about so I sorta share a lot of his thoughts. It's a L-o-o-o-o-n-g read.

http://www.rathcoombe.net/sci-tech/ballistics/wounding.html

Don't let 280Rem hear that you don't believe in FPE......

Some ammunition famous for lower velocity but high retained momentum, deep penetration, and killing big game very quickly include:

7x57 with 175-gr RN bullets
6.5x55 Swede with 140-gr bullets
6.5x54 Mannlicher
.303 Brit with 180-gr bullets
.30-06 with 220-gr RN

And what are the momentum numbers?

Mathematical formulas designed to quantify killing power are on the same level, entertainment-wise, as Americam Idol. They lead to silly misconceptions about how and why rifles kill big game animals, and disguise the fact that wound channels and tissue destruction are what kills big game. Rifles are scalpels, not sledghammers. Bigger rifles kill Cape Buffalo well because big heavy bullets break bone and make large, destructive holes in vital organs.The reason 458's are thought of as better stopping rifles than 375's is most likely because they make bigger holes in stuff. Course you better hit him right with either one, or you are in trouble, regardless of what you are shooting.

When you shoot an elk with a 300 Weatherby, you don't kill him based on a mathematical formula; you kill him because the 300 has enough remaining velocity to expand its bullets at long range, penetrate to the vitals, and cause destruction of the organs immediately necessary for life. Bullet structure (and placement) is far more important in this stuff than energy, momentum, kill quotient, etc. A lighter bullet that penetrates to the vitals, expands properly,and destroys vital tissue is more effective than a poorly constructed heavy-weight that fails to do the same, regardless of its mathematical superiority, and "energy absorption". How else can you explain guys on this web site killing elk at the 500 yard mark with 270's? It ain't momentum, it's bullet placement and structure.

Good post Bob!

+1 Bob..............

The first photo is an exit hole in the off side rib cage of a bull Elk made by a 440 grain flat point Hard cast bullet at a muzzle velocity of 950 fps amd 888FPE



The secound photo is the same rib cage of the same Elk this exit hole was made by a 180 grain fired from a 300 win. Mag,with an impact velocity of aprox. 2600 FPS and 2700 FPE





The descruction in no way relates to the Math.........

A friend of mine kills a bunch of stuff wth 475 and 500 Linebaugh (sp?) revolvers loaded with flat nosed (LBT and Keith) cast bullets loaded to something like 850 or 900 fps on top of a little shot of WW-231. Is that along the lines of what you're running?

mathman

The exit in the picture was made by a 500 JRH in a 5 1/2" barreled Freedom Arms revolver. The bullet was a truncated flat point,with about an eighty percnet meplat I also have Revolvers in 475,and 500 Linebaugh, 454,44 Mag as well. Got my first 475 in 87 or 88 the first in 475 caiuber that Hamilton Bowen built.....
They are desuctive killers of game for sure despite the fact that the hard cast are basicaly mon expanding projectiles

One shot kill and complete pass through (bullet exited),with a 525 grain WLFN out of a 500 Linebaugh at 1120 fps....

22 Short, CB, 29 gr. LRN


Velocity, ft/sec

Muzzle 710
50 yards 656


Energy, ft-lbs

Muzzle 32
50 yards 28


Source: CCI

Conclusion(s): Numbers don't kill. Placement has something to do with it, or so I suppose.