Message-ID: 
Newsgroups: AIRGUN.LIST
I have been trying to determine why a group shifts from right to left as
either heavier pellets are used or the charge drops.  
I keep missing sparrows at beyond thirty yards which I was blaming on the
wind when using my QB77.  I moved to the basement this past week and shot
a lot of five shot groups using various pellets.  The main difference is
the impact location of the group which for the most part is inline with
the weight of the pellets.  Lighter pellets hit about 1/4" high and 1/4"
to the left.  The only exception to this is Mako pellets which also hit
1/4" high and 1/4" to the left.  Shooting Premier lights until the CO2
starts getting week I leave a neat line from 1/4" high and 1/4" left to
1/4" low and 1/4" right.  
The only thing I can see is that the scope is mounted slightly to the
right of the receiver.  Is this the cause of the group shift?  If so how
do you go about mounting the scope centered when you are using clamp on
mounts on the machined dovetail slots?
It's only when you get hold of an accurate rifle that these things come to
light.
Garry
Mid-MO
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