I agree with all those that praise steven segal, no way Id take him on. I would however question the strength needed to drive a Chefs knife through the top of someones skull (under siege 2). I know hes big, I know about technique, timing, etc... (I weigh 300 pounds and am ranked reasonably high in several martial arts) and I would baulk at ramming a knife through someones skull. Maybe if it was a Strong, sharp dagger, with a non slip grip and a big handguard.... but a cooking knife? The potential for sliced and diced fingers is huge
Carnifex.... I am not a handgun expert although I do know a bit. From what I understand, even something like a .454 Casull, loaded with SXT wont Stop a charging human body. The bullets will rip through, destroying tissue and bones (and the guy getting hit will die rather rapidly). It all depends on how close he is, what hes armed with etc. If hes 3 feet away at full speed with a baseball bat over his head when the first round hits him, he will probably still hit you. If hes 15 feet away and you empty the cylinder into him, he will be very dead.
If you can carry a Desert Eagle or a Grissly (to my knowledge the only guns chambered for .50 AE) or a .454 revolver (no autos in this caliber, not for a while anyway.... I think?) on a regular basis (they are damn HUGE), you really shouldnt have that many troubles in a fight.
The only weapon I have fired that would knock someone back was a modified shotgun my uncle had. It was a double barreled 10 gauge. hed cut it down (legally) and replaced the dual trigger with a single one. If you could handle the kick, it would rip someone in half. Hugely impractical, but.....exciting to shoot. If you whipped that monster out, any BG would think about 500 times before attacking you.
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People who say knives are innefective weapons have never been stabbed