Are you serious? You admit you have 'buddies' that take 600 yard shots?
unless you are special forces and have legal arms and training to take that shot....well... I refuse any shot over 175 even though I could drop it at 250.... and have not made a shot over 100 yrds in several years..
I did A Guy in LOUSE at a 1000yds...NutZ..It was the only thing I was ever good AT!