300 Win Mag. Its been around for a long time and you can buy bullets for it anywhere. The 300 Win Short mag is the flavor of the month. It is a shorter fater version of the 300 Win Mag with out the belt. It was designed for shorter actions. 300 WSS.WSSM is a balistic side step from the original 300Win Mag and only time will tell if they stick around. One thing is for sure the 300Win Mag will always be around. The 300 Win Mag isnt as punishing as the 300 Weatherby. The 300Win Mag will take any big game down quickly way past 200 yards.