Gun is a mk2 impact with a 500 mm superior liner.
Shoots .216 nielson 20.2 slugs at 990 fps.
Groups were at 100 yards.
Wind was very favorable at 0 to 1 mile an hour.
Temp around 85.
I have owned this gun for over 2 months and knew it drove tacks with the nsa slugs at 50 yards, and I had greased numerous prairie dogs at 120-170 yards so i suspected it was pretty accurate at 100 yards. Needless to say, i am exceedingly happy with the results.