I have been shooting for a number of years now, furthest recorded kill was 623 yards. I have Browning a-bolt 300WM factory barrel with a nikon buckmasters 6-18x40 BDC and looking to upgrade to a new scope and mount setup. I am wondering what are the big differences between the Vortex Viper 6.5-20X50 PA and the Viper PST 6-24x50? I have heard a lot of great things about the vortex scopes so any of your input would be GREATLY appreciated!! Also what mounts are you using with these scopes? Which would you suggest i go with. not quite shooting 1000 yds but within a year or 2 would like to reach that achievement. Also i was looking at the Leupold VX-3 6.5-20x40 any input or suggestion on how it compares to the vortex?