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From: (Bart Bobbitt)
Subject: Re: EndFeild/6.5 Muaser
Organization: Hewlett-Packard Fort Collins Site

Dan Chisolm wrote:

: But say you're shooting a 10-shot test string, and call one
: shot out to the right.  Sure enough, upon later examination, you have
: one out.  Do you:
: 	a - consider the rifle/ammo to have shot the large group
: 	b - throw out the group as irrelevant, due to shooter error
: 	c - accept your call, and discard the called flyer.

What I do is not listed as an answer.  When testing at 1000 yards, I have
someone pulling targets for me.  I put a 3-in. white spotter on a 5-in.
black spotter as an aiming point.  Quartering this point with my scope's
crosshair, I note the relative position off from dead center for each
shot.  When the target is pulled down after each shot, this off-dead-center
call is noted and the direction is reversed with the same magnitude on the
shot hole.  This makes each shot's location reasonably correct relative to
the aiming point.  Bad calls are easily corrected for by doing this, but
you have to verify each shot location after calling it and before the
next shot is fired.  After the shot group has been corrected for calls, I
call it the corrected group.

I name the off-dead-center aim points a `call group.'  When plotted on paper,
it is smaller than the shot group.  If the call group is 25% as big as the
shot group, it's possible that the call group is only 50% as big as the
corrected group.  Sometimes it isn't, but that's life.  To get an accurate
evaluation of the rifle/ammo performance, I think the fired shot's location
relative to where the rifle was aimed is the most important thing.  Very,
very few folks hold a rifle perfectly still from a bench and nobody can in
position.  I don't have a small call group when shooting from a bench; I
just don't have a good technique.  At best, I'll have a half-MOA diameter
call group from a bench.  From a prone postion with a sandbag under my
front hand and one under the stock's toe, my call group's about a tenth-MOA.


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