a year ago, in an exchange of correspondence, a friend asked my
opinion of how shotgun pellets kill.
was my reply:-
my opinion, lead shotgun pellets do not kill by energy transfer by
deformation. Let me explain: A bullet, whether a simple hollowpoint
lead 0.22 rimfire, or a centrefire semi-jacketed softnose, when it
passes through animal/bird tissues, creates enormous shock waves
which destroy not only the tissues, through which the projectile
actually passes but also adjacent tissue to the bullet’s
trajectory. These "shock" or "stress" waves have
been photographed and I think the Swedish Cartridge Company Norma
published some of these photos in one of their bullet brochures a
few years ago.
very low velocity of shotgun pellets, whatever the shot material,
combined with their relatively small size is not sufficient to cause
any shock wave injury outwith the pellet channel other than very
minor damage. Evidence for this you can see yourself - all you will
see is bruising in the area around the pellet entrance hole. The
reduced velocity after entry restricts the shock wave damage merely
to a channel of destroyed tissue along the trajectory of each
pellet. It is this restriction of damage which means the injury is
related only to the muscle and organs penetrated by the channel of
is why I believe that wet wood pulp (in the guise of telephone
directories) is an excellent tissue simulant. Wet wood pulp is very
fibrous and in many respects similar to animal tissue. If you
examine a pellet extracted from animal tissue you will observe the
pulverised, fibrous, tissue adhering to it – a similar occurrence
is seen in a pellet extracted from wet wood pulp.
kills the same way as lead but, unlike lead, it does not deform on
impact. In fact, I also suspect, based on my microscopic examination
of shotgun pellets, that lead does not actually deform very much on
impact (other than when hitting bone) either. I am pretty sure that
most of the deformation observed in recovered shotgun pellets is due
to the initial ignition set back forces.
a nutshell, I firmly believe that all shotgun pellets kill
by penetration of vital organs, not by energy transference
due to deformation. Steel, by nature of its lack of deformation is
simply more efficient in penetration and thus probably kills better
than expected, despite its inherent density shortcomings, and
certainly better than any ballistic theory or tables would suggest.
I wrote was, I believe, simply commonsense. It amazes me that some
wildfowlers actually believe that “shock” has something to with
killing wildfowl. It further amazes me to have discovered that
apparently so few people examine in any detail the quarry they
actually shoot – if they did then they would have a better
understanding of what actually kills.
Roster (see endnote) in the USA, with the largest lethality database
in the world, has frequently stated that, to avoid wounding, one
needs a sufficient number of pellets that have sufficient energy to
penetrate the vital areas – i.e. brain, cervical and thoracic
vertebrae and heart.
recently, David Leeming of Cranfield University at the Royal
Military College Shrivenham gave a paper (see endnote) at the BASC
National Wildfowling Conference early in 2002. In this paper, David
Leeming gave a really excellent essay on penetration and lethality
and I commend all to read it.
the days when all our shotgun cartridges contained lead, things were
had to decide on the size of shot suitable for the target quarry
species and the maximum range at which one was accustomed to shoot.
The wise wildfowler patterned his gun with various shot/choke
combinations. Now, with non-toxic shot being mandatory in the USA,
Canada, much of Northern Europe, England & Wales, there are
all pellet materials, behave equally. For that matter, neither does
lead. Low and high antimony lead pellets behave differently too –
antimony being alloyed with lead to maintain better sphericity
Impact Tungsten Matrix, buffered and unbuffered, Steel, Hevishot
(Iron, Tungsten & Nickel), Tungsten Iron and other metals
currently under development, will all behave differently. With this
in mind it is surely our responsibility to pattern our own guns to
determine the pellet count at the ranges at which we habitually
shoot. In a previous article of mine in Wildfowling International I
describe how to do this.
pattern your gun at the range at which you normally shoot. (I
pattern my gun at ranges 30-45 yards) Once you know how many pellets
you averagely get within a 30 inch circle with the
gun/cartridge/choke combination that you use, it is time to consider
the SIZE of the quarry you shoot.
the USA, CONSEP - Co-Operative North American Shotgunning Education
Program have produced a chart (see endnote) that recommends the
appropriate steel shot size, pellet count for various quarry species
within various range windows. This chart is based on the literally
thousands of autopsies carried out on wildfowl in which the range at
which the shot bird was known.
wildfowlers have only a general idea of what constitutes the vital
target area of the variety of quarry they shoot. Additionally, in
some of the literature, erroneous or confusing information has been
given. Some writers and researchers refer to VULNERABLE areas,
others refer to VITAL areas and, unfortunately, they often use both
terms in the same paragraph without distinction.
is not simply a matter of semantics. There is of course a
fundamental difference between vital and vulnerable: "VITAL”
is ESSENTIAL to life - and if a vital areas are penetrated it is
almost certainly dead. “VULNERABLE”
simply means exposed to potential harm. Therefore being inconsistent
in terminology leads very easily to confusion or misunderstanding.
the literature, time and again, one sees reference to the
“vital” area of a mallard as 20 square inches. This is surely
incorrect. Cochrane (see endnote) correctly describes the vital area
of a mallard as 12 square inches.
Doubt this? Look it
another way……Take out a mallard from your freezer then measure
the approximate broadside surface area (i.e. you are measuring the
defeathered, eviscerated, headless, wingless, & legless duck)
Trying this yourself you can will discover that you get something in
the region of 20 square inches. Cochrane’s lower figure was, I
believe, measuring correctly the VITAL areas i.e. those which, if
penetrated by a pellet, would certainly kill.
My wife and I took the trouble to measure the VITAL areas of
a considerable number of my most common wildfowl quarry species,
last season. Our measurements showed that the vital area of teal was
4.9 square inches, for widgeon 8.2 square inches and for mallard 12
square inches. These measurements are the average values for male
and female combined. The vital areas measured were brain, cervical
and thoracic vertebrae and the heart.
have found that if one or more pellets penetrate THROUGH one or more
of these VITAL areas the quarry will be instantly killed. Failure to
penetrate the vital area will not result in instantaneous death and
pellets penetrating “vulnerable areas” (a broken wing bone will
terminate flight) may result in bagging but only at the expense of
wounding first. Pellets penetrating non-vital areas such as the gut
will only result in wounding and a lost resource.
synergistic effect of two 4.00MM steel pellets penetrating vital
areas of the greylag goose ensured instant, dead-in-the-air death.
all ranges, whether short, say 25-30 yards, or long, 40-45 yards, we
should each get to know what our gun can and cannot do by carefully
patterning the gun. Please do not assume you will achieve the same
pellet density at any given yardage with the same load of bismuth
and ITM – you will not. Do not assume that small steel shot, less
than 3.6mm in diameter will pattern tighter than lead or bismuth –
it may not.
is tedious but there are no short cuts. Take time to examine your
retrieved quarry – was it instantly killed or merely wounded
before despatch? What was the range at which you shot? Take time to
practice judging range accurately. Instead of taking a longer or
high “sporting” (?) shot, take pride in your marshcraft and take
the shot at modest range when BOTH penetration through vital areas
and pellet density is at its optimum to ensure instant kills.
wildfowlers and conservationists we must do our very best to ensure
that not only do we bag what we shoot but that the highest possible
component of that bag was killed instantly.
1976, Wildlife Monograph No 51, Crippling Effects of Lead, Steel and
Copper Shot on Experimental Mallards.
CONSEP Chart 1999: http://dnr.state.il.us/waterfowl/files/pg20pdf
and the 2001-2002 chart http://wildlifedepartment.com/waterfowl.htm
David Leeming, BASC
National Wildfowling Conference 2002, Shotgun Characteristics for
Clays & Wingshooter Magazine, December 1998 Patterns VS.
Penetration, Part one, pages 22-24, 26, 28, 30-31. And Part two,
January 1999, pages 38-39, 76-79.