I had an old piece of metal deck from the scrap heap.
Wanted to see how well penetration occurred with .224 and .312 fmj's.
You can see where only one 556 round did not completely penetrate the deck plate probably because the round struck next to a previous hit which may have slightly hardened the surrounding area of the metal + it was right on one of the treads.
Interestingly enough, the impacts are nearly the same diameter from the front but can more easily be distinguished from the rear.
These were 55 and 174g pills @ the 300yd butt.
Bullet jackets remained from both rounds at the point of impact with very little
evidence of post impact exterior spalling and no sharp petals remaining at the rear.
Wanted to see how well penetration occurred with .224 and .312 fmj's.
You can see where only one 556 round did not completely penetrate the deck plate probably because the round struck next to a previous hit which may have slightly hardened the surrounding area of the metal + it was right on one of the treads.
Interestingly enough, the impacts are nearly the same diameter from the front but can more easily be distinguished from the rear.
These were 55 and 174g pills @ the 300yd butt.
Bullet jackets remained from both rounds at the point of impact with very little
evidence of post impact exterior spalling and no sharp petals remaining at the rear.