I jokingly say until I joined this forum I never knew there was any other cartridges than the 30-06.I've had 2 06s. Both were purchased the same day in 1945 in a hardware store in downtown El Paso by a pair of brothers. Both were Winchester Model 70's. One of the brothers was my grandfather the other my great uncle. My grandfather and Bill Weaver (Weaver scopes) were friends and hunted together and Mr Weaver was instrumental in getting my grandfather to put a scope on it. That scope is still on it and is still a very nice hunting scope. My uncle left his unscoped and he was an exceptional shot with that gun taking coyotes, deer and antelope out to 500yds. I acquired both guns after my grandfather and uncle had passed on. I kept and used them as they were for years and then gave one to each of my two sons. They both still have them and use them. If my eyes were better I would borrow the unscoped gun and give Cortina's 500 yd challenge a try.