Shooter has training and knowledge.
I have not had time to run the numbers and won't for a while.
I will still trust a .223 or a .308 through a playing card.
Since you didn't address that comment to me, I missed it. That's pretty good. I'll have to remember that one.
As Eaker said: Agreed. I was adding a bit of information when people talk about brush busters. Yes, It will go through brush. It just may fail as to where in the brush it may wind up.
This subject had come up once in a while and I have spent hours looking for that particular picture without success. The closest I can tell each of you is kind of a humorous portion of a video that was sold a long time back called "Deadly Weapons". It was a entertaining video with no real science to it. They put some brush in a pile and tried to shoot through it. Some rounds made it and the narrator was shocked that a .50 BMG was deflected. The look on his face was funny. I mentioned the .50 before but I thought I would elaborate on it some more.