I started with a BB rifle with mine ,then a 22 , I had to ease my nerves into it !!
More gooder readings at 15-20 feet, muzzle blast made me pull all my hair out until I figured it out.
On a real brite day I use a translucent 5 gal bucket to difuse the lite.
Also I use skewers marked hi enuff for a scope to line up with .
The skewers break when hit the steel rods jerked mine of the table when hit ! & NO there were`nt a hole in the chrony !!!
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