I use these in .45ACP.. fully functions in semi-auto (M&P) Only drawback is you have to be pretty close- the spread is very wide (which is also an advantage)
But if you're far enough away you have that much warning, then a shotgun is probably a better choice.
ΜΟΛΩΝ ΛΑΒΕ, we are the III%, CIP2, and some other catchphrase meant to aggravate progreSSives who are hell bent on taking rights away...