Re: Kinetic Energy Required to pierce 0.5" Steel
First, what kind of steel? Mild steel is very easy to go through. AR500 steel, not so much. I bought some cheap mild steel targets (about 5/8" thick) for our range. Anything closer than 300 yards with my 300WM with 190 SMK (at 2970 fps) will go through it.
Also, I don't think it's kenetic energy that causes the penetration. It has to do with the size (diameter) of the bullet and how fast it's going. I believe it's the heat that's built up from the speed of the bullet that allows the bullet to go through the steel. If you fire a fast 223 Rem bullet (55 FMJ at 3200 fps) into steel, it will go through it like butter. But, if you take a 44 mag (240 grain at 1400 fps)and hit the same plate, you will only put a large dent in it. They both have about the same energy. The larger bullet spreads it's force out over a larger area. I'm not a chemist or such, so I can't give a technical explanation. Maybe someone can chime in more on this.
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