And laugh if you want, but a freshwater mussel at 1300 FPS would mess you up! And it has to be pretty terrifying for the mussel also.
I had the privilege of watching chickens shot out of a canon into aircraft windshields. The chickens were taken out of the freezer, thawed and put into the canon. They hired a newbie but did not give him much instruction on how to do the testing. He put a frozen bird into the canon. Instant windshield failure. So..... I would suggest you use a frozen fresh water mussel if you want to exercise you 2nd amendment rights.