I just shot my first silhoutte rimfire match to 100 yards, using a slabside and an UltraDot. I was able to clean out (almost) the chickens & pigs up to 50 yards. Then I ran into problems with the turkeys & rams at 75 & 100 yards. Tried less ilumination & it helped some. Shot about 30-40% of the targets at 75+ yards. That red dot sure looks big at 100 yards! There was a guy with a 10" barreled Ruger using iron sights, who fared rather well; but most used regular magnification scopes. I think I will start shopping for a 4X.