How long have you had that printer paper laying around? Nice work on the shot patterning.
Sometime around 1996 or 97 a Staples store had these on closeout, $5 for a case of 5000 sheets. I use these for load workup and general target shooting and use a Sharpie to draw whatever aiming point seems appropriate. The other side has alternating color bars 1/2" apart which helps when sighting in and such. Plus, if dot matrix printers every make a come back I'll be ready...