FEBRUARY 1995

THE TECHNOID TAKES GAUSS... Your new Holland and Holland
sporting clays gun was specially choked in England by a famed
necromancer of that black art. You paid extra, but you got the best.
You are certain that its patterns will be superior to the old Mossberg
lurking in the back window of your pickup truck. Well- 'taint
necessarily so. This is deep stuff, so pull on your boots and step in with
the Technoid.

You see, shotgun patterns, Holland's and Mossberg's together,
are Gaussian in nature. Carl Gauss was a late eighteenth century
German mathematician who contributed greatly to the knowledge of the
bell shaped curve, also called a 'normal' distribution. Most succinctly,
he showed that certain seemingly separate random processes, when taken
as a group, act in a predictable manner. This predictable manner is
called a 'normal' distribution and is mathematically and graphically
expressed as a bell shaped curve.

So, what does it mean to us as shooters? At the end of the
nineteenth century a French ballistician named JournÇe was doing some
work for the French army. He noted that when many rifle bullets were
fired at a single target, the highest percentage hit near the center and
then the hits became fewer and fewer as the distance from the center
increased. Careful analysis of many such targets showed that the bullet
distributions mathematically followed Gauss's bell shaped curve and
produced a 'normal' distribution. This was significant because it meant
that such seemingly random clusters of bullet holes were regularly
obeying unyielding mathematical laws when taken as a group. It meant
that statistically JournÇe could predict performance of groups of bullets.
Although each bullet fired was a random event, together their group
performance was predictable.

Cut to the 1970s. Mid-western graduate students Oberfell and
Thompson wrote a scientific book on shotgun patterning, which has been
considered a leader in the field for the past twenty years. In it they went
to extremes to calculate the difference between good patterns and bad
patterns based on the number of 5" holes in the pellet spread. They
attempted to show that proper load development and choking could result
in a shot pattern with a more even distribution and fewer holes, even
though the total percentage of shot in the circle was unchanged. They
felt that one 60% pattern could be better than another 60% pattern
because shotgun pellets worked in concert with each other. There was
sort of a group influence, as opposed to JournÇe's bullets randomly
functioning as individuals.

Recently, shotgun ballisticians on both sides of the Atlantic
(Messrs. Lowery, Giblin and Brindle) have concluded that the shot
pellets, once well clear of the barrel, act independently- like JournÇe's
bullets. Each pellet is on its own and subject only to the higher law of
the bell shaped curve. Oberfell and Thompson's idea that there is a
repeatable group harmonic is rejected. This means that no matter what
you do, if you shoot enough patterns with the same total pellet count in
each pattern (that is important), the number of 5" holes (pellet
distribution) will even out and follow a bell shaped curve 'normal'
distribution. There is no such thing as a consistently high quality or low
quality pattern just as long as they all have the same number of pellets in
the same sized circle.

For example, let us say that you find a load and choke
combination from your Mossberg which produces a 60% pattern at 40
yards. You then shoot 100 patterns. Then you find a choke and load
combination (same pellet count) which shoots a 60% pattern from a high
quality, custom choked gun. You shoot 100 patterns. If you compare
those 200 patterns, you will find that the custom choked gun produces
60% patterns which are no better or worse than the 60% patterns
produced by the cheaper gun. They will both follow the normal
distribution of the bell shaped curve and the number of 5" voids will
average out equally from both guns.

If all 60% patterns of the same pellet count and in the same circle
average the same number of holes in the long run, does this mean that
there is no difference between low quality chokes and cheap shotshells as
opposed to the good stuff? Not hardly. There is a big difference.
Custom chokes and high quality shotshells are worth it because they
enable you to achieve a certain pattern percentage performance which
may be totally unobtainable with inferior equipment.

Good chokes and good shot may achieve a 60% pattern with a
.020" (modified) choke. Cheap chokes and shot may require .035" (full)
choke to reach that performance. At this stage the patterns would be
mathematically equal, both following the same bell shaped curve.

Now look at the next step and suppose you want a 70% pattern.
The good choke/good shot combination can achieve 70% by using
somewhat more constriction. The cheap choke/cheap shot cannot
achieve that number by any means. The difference between good and
bad has just emerged. The bell shaped curve no longer applies because
the poor equipment cannot deliver the basic percentage required.

The equipment quality difference becomes even more pronounced
when shot string on a crossing target is considered because that makes it
even harder to produce a pattern of a given percentage. That bell curve
equality only applies when each shotgun can achieve the same percentage
and the cheap stuff often cannot achieve the high percentages.

So what is the bottom line? There is no statistical difference in
patterns of the same percentage, regardless of which shotgun produced
them. There is no point in counting holes in the pattern, just count the
pellets in the shot load and then in the circle. Cheap chokes and
shotshells can be made to equal the performance of good equipment up
to a certain distance. At longer range good equipment wins out.

Junior Technoids- At Ease! Take off the boots, you are now
clear of the bovine remnants.

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