King? Worldwide use may suggest the 7mm Rem Mag is probably the holder of that title. Does anything and more than the 6.5-06 and enjoys the popularity of buying ammunition any place around the globe. From 100 lbs - 1,500 lbs of game animal, probably none have been used more successfully than the 7mm Rem Mag. Hard to beat and with today's bullet choices as it is better than ever.
I think if you look into it, 30-06 still holds that title.Last time I saw a chart, it looked 30-06 ammo was the biggest sellar
