For forty years I have read, and pondered, over a multitude of writer's
thoughts on bullet performance in living tissue. I find that they fall in two
classes - light bullets @ high velocity & heavy bullets @ low velocity.
These two classes developed formulae to backup their own observations and
within their categories they were correct. However, when they attempted to
relate to the other class, they were trying to compare apple to pears!
First we must understand the properties of common water! Water is a
solid in liquid form! It can not be compressed, therefore only moved! Drop
the temperature it becomes a solid, apply heat and it vaporizes. Since living
tissue is comprised mainly of water, understanding its properties are
foremost, in equating it to bullet performance. Forget, for a moment, all of
these formulae, and think only of a projectile moving through water. Since it
is a solid in liquid form, it must be moved (displaced) by a projectile. The
rate at which it is displaced governs all forms of wound volume and
channel! In HVLW( high velocity-low bullet weight) situations, this rate
is high (but quick), whereas is LVHW (low velocity-high bullet weight) this
rate is low (but slow). Energy is released by deceleration also. These two
factors use up KE, but in opposite forms!
As an expanding bullet mushrooms, or fragments, the deceleration is extremely
fast and displaced water velocity equally as fast. Ergo...short length and
high volume wound area. This is one side of the equation. The other side
is....LVHW displacing water with less perpendicular water movement and over a
longer period of time (Energy Deposit Dwell Time). Ergo....long length and low
volume wound area. This, of course, is the other side of the equation. When
looking at this equation, we see where the two philosophies part company. They
are both correct in each of their evaluation of desired bullet
performance!! It is at the balance point of this equation ( I feel @ .35
caliber +-) that the mass of the animal must be taken into consideration!
On the side of HVLW, bullet construction is critical! On the side of LVHW,
bullet shape is critical! Since we are dealing more with LVHW, I will
continue with the latter part of the equation.
In LVHW there are two critical factors....Sectional Density for penetration
and Meplat for water displacement. There are three basic bullet nose shapes
involved in LVHW . The Round-nose is the oldest and most common, but the
poorest for water displacement ( permanent wound channel). Next is the Pyramid
Nose, somewhat a compromise in penetration and permanent wound channel. The
third is the wide meplat bullets of Beartooth. It's precisely at this point
our people (LWHW) start arguing!
Marshall has politely tried to impress on our people that meplat was more
important than too much penetration. This was what I was trying to show with
small difference in the permanent wound between 1000 '/" and 1500
'/" with the 250gr .430" LFN GC( meplat @ .300") bullet. With
this in mind...I want you to run up the difference between the 185 gr .358 FN
GC meplat with .280" meplat @ 1450'/" and the Keith 250 gr
.430" with .280" meplat @ 1200 '/".......as far as Permanent
Wound Channel. The latter was Elmer's favorite .44 Special load. Change it to
1400'/" and you have his favorite .44 mag load. So the point here is how
much penetration, recoil, blast, etc., you desire!
If you take a piece of graph paper and put two vertical lines 10 inches apart,
labeling one at Velocity ( 10 inches high) and opposite side a vertical line
labeled Weight (10 inches high) and use this as a box graph....by plotting
known cartridge velocity on one side and weight on the other...and connecting
the lines....you find some interesting points of intersecting lines of the
before mentioned equation.
So....We know that increasing the meplat of the of the bullet there is
increased water displacement and from this comes tissue damage!!!
Best Regards as Always....James
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