I first mounted a scope on my slug gun back in 1980, it was a Weaver K2.5 with a post and crosshair reticle. This served me well for many years, I have also had a Weaver K3 with medium crosshair and LEE dot. My scope of choice is a Weaver V4.5 with duplex reticle, this is what is currently mounted on my slug gun and has taken several bucks in all kinds of conditions. All of these scopes can be found on the secondary market for $100.00 or less.