Actually, given recoil and bullet spread, it probably took something like a dozen rounds. The guy who would be holding the sword, on the other hand, would have more holes then swiss cheese from the hundreds of rounds that went by and hit him.
And lo, is the problem. Unless your lucky enough to get the drop on the guy, in the time it takes you to close distance and swing the sword he will have put at least five rounds through your body. And if you do get the drop on him, you better pray he doesn't have a buddy or you will be quite dead before you have even finished fully finished the blow.