@Gibbedboy I own a Mosin nagant that uses standard surplus 7.62 ammo will go through 1/2+ mild steel railroad tie plate and keep going at 100 yrds. My wifes 5.56 does the same so 2cm (approx 3/4 in) mild steel/hammer forged or cast iron will not stop it and that's not getting onto armor penetrating ammo.
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