May I ask why the OP is selecting Winchester Short Mag's over the conventional cal. if he is limited to factory ammo's??

The reason I ask is because I see no advantage to the Short mag's or even Super Short Mag's if limited to factory ammo. With prices (on factory ammo) higher than the old .270 win. why buy the Short Mag or even Super Short Mag at all?
Unless you are a reload er, then that changes the whole ball game here.