by Jim Taylor
Most people who shoot for very
long soon begin wondering about the power of their guns. When the bullet
strikes its target how hard does it hit ? What is the effect? Is
it more powerful than.......? Every once in a while
"discussions" get going as to which gun/load/caliber "hits the
hardest" or words to that effect. The question is basically the
same no matter how it is phrased.
Ammunition companies have supplied
kinetic energy figures with their ballistics data for years. This is in
the form of "foot-pounds" of energy, usually written as "ft.
lbs." in the manuals. And when you read that the .308 has 2460 ft.
lbs. of energy at the muzzle compared to 1350 ft. lbs. of energy for the .44
Magnum sixgun, it looks like the .308 would be LOTS more effective at killing
deer or game than the .44 would be.
But... as with most things, there
is a problem with the foot-pounds theory of bullet energy. To begin
with, the definition of "foot-pounds" is: "a
unit of energy, equal to the amount of energy required to raise a weight of
one pound a distance of one foot." ( Webster's) Anyone who
has ever played around with firearms for very long has discovered that a gun
with "2000 ft. lbs." of muzzle energy will not move 100 pounds
sideways 6" let alone lift it a foot!
Here's an experiment for you to
try. Fill a 5 gallon bucket full of sand. Set it on the ground and
shoot it with your rifle that has over a ton of muzzle energy. Let me
know if it moves it all. If the foot-pounds idea were correct, the
bucket would go flying. But it will not. Suspend it on rope 3 to 4 feet
long, and shoot into it with your super-duper belchfire Magnum and see how far
it moves it. Not much I can tell you right now.
Lest you think I am against using kinetic
energy measurements ("foot-pounds") let me state that it is useful
for comparing certain loads to each other. But I would stick with the same
caliber when making comparisons. It almost useless when it comes to
other areas and often leads to misconceptions when it come to pitting one
gun/caliber against a different gun/caliber. Such as comparing the .44
Magnum revolver to the .308 rifle. While the rifle is without question
more powerful, when it comes to dropping game the .44 handgun will do the same
job the .308 does, within limits. If you were to use both guns shooting
at the same animals at comparable distances ( under 100 yards say ) there
usually is not a discernable difference between the effect of either gun
on the animal when hit in basically the same spot. I make that statement
based on my experience shooting animals over the last 35 or so years.
Over 30 years ago I was sitting
around with my Dad and some friends and we were discussing the subject of
hitting power. We decided we would experiment a bit. It gave us an
excuse to shoot! We went out in the yard, nailed an 8 foot 2x4
onto a log that weighed about 20 pounds and hung it from the clothesline.
We shot a few guns into it and were mildly surprised that none of them moved
it very far. The .300 Winchester Magnum only moved it 6" or
so! (all the bullets stopped in the log so it soaked up all their
power ) Dad took a 20 ounce claw hammer and whacked the end of the log
as hard as he could and it moved it about 6". So we concluded the .300 Magnum hit about as hard as a whack with a 20 oz.
claw hammer. Now that is nothing to make light of. But it isn't nearly a ton and half as the kinetic energy figures would lead us to think.
I decided to get serious about
this - this was in the ancient days before personal chronographs - so we
built a frame from which we hung a 48-pound mesquite log. It was hung on
a 6-foot long arm and had a tape fixed to it to accurately measure the
movement of the log. The log stopped all bullets fired into it. We
figured out what loads we were going to shoot beforehand and had bullets of
equal weight on the log. When one was fired into the log, one was
removed keeping the weight of the log the same. It probably was
unnecessary, but that is what we did. What we found was that some
handguns hit just as hard as rifles. This
confirmed observations on game in the field.
If you watch the Anite Productions
video DEADLY EFFECTS, the producer of the video takes a point blank shot
on a vest with .308 Nato ammo .. WHILE BALANCING HIMSELF ON ONE LEG!
Just to prove that the actual hitting power is not all that hard.
It don't knock him down. He actually does it twice on the video just to
make the point.
I know someone will bring up the
fact that the energy is "dissipated" over time and distance, or
other such arguments. Think about it. The bullet STOPPED on the vest.
All energy was expended. The .308 has over 3000 ft. lbs. of muzzle
energy. Over a ton and half. Even if the bullet "lost" a
ton of energy magically, somehow dissipated into the vest, it still should have
enough power to knock over a 175 pound man balancing on one leg!
In our tests shooting the log, the
log absorbed all the energy the bullet had, even if it did take a few hundredths
of a second. Don't try to argue that X amount of energy gets turned into
heat, while X amount of energy moves wood particles or peels the jacket back
or whatever. It's all inside the log and happens in an incredibly short
space of time. Even if 3/4 of ton of that hypothetical ton of muzzle
energy was siphoned off by the bullet coming apart in the log, 1/4 ton of
energy should still move it more than an inch or two!
We did not actually prove anything. However it was fun to do. What we were
measuring is called "Momentum Energy" by those who are better at
math than I. Momentum is the amount of "push" a
moving object has. Obviously the weight of the moving object is a big factor,
influencing the results more than velocity. With kinetic energy figures
velocity is the big factor which influences the results. There are other
method of figuring hitting power, such as the "Taylor Knock Out"
theory. It favors caliber. All such thoeries have their drawbacks and limitations. They are part of
the quest to find a way to put down on paper what we observe in the
And .. all the different ways of
measuring a bullet's power are interesting. The best way though is to
get out in the field and do it up close and personal.
RECORDED MOVEMENTS OF A
48-POUND PENDULUM ON A 6-FOOT ARM
(all shots were fired at
15 feet from muzzle to the pendulum)
||125 gr. FMJ
|357 Magnum 2 1/2"
||Rem. 140 gr. JHP
||Super-Vel 110 gr. JHP
|357 Magnum 6"
||Super-X 158 gr. lead
||Super-Vel 110 gr. JHP
|44 Special Charter Arms
||Rem 246 gr. lead
|45 ACP Model 1911-A1
||230 gr. Hardball
|45 Colt 7 1/2"
||WW 255 gr. lead
||300 gr. handload
|44 Magnum 7 1/2"
||Rem. 240 gr. JSP
||Super-Vel 180 gr. JHP
||Rem. 170 gr. JSP
||WW 150 gr. JSP
The big winner of the day was the
old .45-70 cartridge. I shot some original UMC blackpowder loads with
the 550 gr. bullet. These pushed the log 5 1/16"! Of course,
as I stated above, bullet weight is a big factor in this kind of testing.
What does it prove? Not
much. A hit in the right place with a decent load will do the job.
A miss with a Magnum is still a miss. Nothing can replace expertise.
However, on those long winter evenings when you are sitting around with
friends and the subject of which gun is more powerful comes up, here's another
way to start an argument.
Above - a much younger Jim Taylor
firing an 1886 Winchester 45-70
into the log.
Right - the pendulum.