OK, now we are talking about the length of the magazine, not the action. As far as I know there is a short action, which seems to be everyone's favorite these days for one reason or another. New cartridges are designed to be short and fat. Reasoning seems to be to cut the weight of the rifle and the time it takes to cycle the action for a second shot. Well, the weight savings are in ounces, not pounds and the cycle time difference is in microseconds for an experienced shooter. All in all the quest for short fat cartridges, to me, and maybe me only, seems to be a waste of time.