Show on Sportsman channel last night- looked at knockdown power. Set up a concrete block, couple bags of sakrete behind standing on their sides. They fired 9mm, 40, 45, 223 and even a 7.62 and none of them knocked down the concrete block.
They didn't try rskahle's 10mm.
I really didn;t think much of the 'test'...I mean, all the rounds entered the conc block, but it's nowhere nearly similar to hitting a man in the chest. I kinda agree, knockdown power is not to be expected, stopping is the issue. And shot placement is the best test for that.