The March 20 edition of Warrior Connection was a discussion based on
the Army Times front page story for March 21 edition "TOO MANY SOLDIERS
CAN'T SHOOT" ( Army Times pages 18- 21, Michelle Tan) and how to improve
personal marksmanship with either a rifle or handgun. Obviously, we
think that everybody should qualify as an expert but that will take time
and increase costs. Supporting commentaries we have written include:
Practical Ballistics for Self-Defense - Doug Rokke
The decision to use any rifle, handgun, or shotgun for self-defense
entails legal justification according to state law and the selection of
ammunition that will ensure that you win the gunfight. Just as old
saying goes “you don’t bring a knife to a gun fight” you should select
ammunition that will immediately end any gunfight that you are in. That
means knocking the person or vicious animal down and out with the first
or second shot. This is commonly referred to as “stopping power”.
The two primary physics concepts associated with ballistics are kinetic
energy “K.E.” and momentum “p”. The laws of physics require that energy
and momentum conserved. That means that for protection we should select
ammunition that deposits all of it’s energy/momentum into the target
but that still has enough kinetic energy or momentum for penetration and
to ensure the knock down-kill. Both kinetic energy and momentum are a
function of bullet mass (grains) and velocity where:
K.E. = “1/ 2” x “mass” x “velocity squared”
“p” = “mass” x “velocity”
Another
important factor is “expansion” or how much the bullet deforms upon
penetration to create a mortal wound channel as it transfers all or part
of it’s kinetic energy and momentum into the target. Ideally any bullet
would enter the target (penetration), fully expand, and transfer all of
its energy into the target and thus stop before exiting out the other
side. That is why a 12 gauge shotgun with slug, double “0” buck, or even
#4 shot is so effective at close range and the obvious first choice for
self –defense. The wound channel is huge and usually mortal because
virtually all of the shotgun shot’s or slug’s energy is transferred into
the target over a large entrance diameter thus immediately ending the
gunfight because the slug or pellets rarely penetrate all the way
through the target.
However, for many reasons the handgun will be
the weapon that is used in most self-defense situations- gunfights.
Today, self-defense handgun ammo includes: .25 auto, .32 auto, 9 mm, .38
special, .357 magnum, .40 S W, .44 magnum, .45 auto, and .45
colt. Gunfights with a handgun will occur within 25’ so we need to look
at muzzle energy and even more effectively muzzle momentum and bullet
expansion. Ideally we want to select a large caliber “heavy mass”
bullet, with excellent expansion, and enough muzzle velocity to ensure
penetration through clothing. High velocity, small diameter, and low
mass bullets tend to zip right through targets at close range with
minimal stopping power and create too much risk to bystanders. Thus the
stopping power of a .45 auto/colt or .44 magnum is far better than for a
.38 or 9 mm with a .357 magnum in between. As we select ammo please
remember that any bullet less than 100 grains when combined with
possible powder loads just does not provide the necessary energy
required for a probable one or two shot kill. However, no matter what
handgun and bullet caliber you select you must practice, practice, and
practice after going through a certified qualification course to teach
you the fundamentals. GSL instructors conduct numerous courses
throughout the year (www.gsldefensetraining.com).
Spraying rounds from large capacity magazines is simply too dangerous,
inadvisable, rarely stops a gunfight, and is probably on shaky legal
grounds too. Simply, if we face a situation where escape is impossible
and the “perp” is ready, willing, able, and intent on ki