Which pretty much tells you why, since wadcutters have been around for so many years, none of the "big three" ever thought to load one backwards as the ultimate in defensive use....
Just like so many of the ninny crowd today forgets the word "illegal" precedes the word "immigrant".......a lot of people tend to overlook the word "controlled" before "expansion" is necessary.
I found the WC thing out by shooting rats with a .20 cal/5mm Sheridan pellet loaded backwards in my Blue Streak. Loaded the right way, the rats dropped like a stone. Loaded backwards, the rats ran away after I hit them.