I didn't really test it out but, when I had it off the rifle, I tried it at the accomodation shed and shone a bright spot on the side of the shearing shed about 50m away. It would easily work on a scoped rifle at this distance, and likely much further. With holidays coming up, I'll see if I can get out again somewhere to test it fitted to the rifle. I don't live far from a rifle range and may check with them to see if I can do this - I don't have to fire shots, and the known ranges of the target frames would be useful.