My rough understanding is that lvl 3 plates will stop up to .30-06 fmj, while lvl 4 plates will do the same but for AP rounds.
300 win mag 6.8 fury, and probably even 6.5 creed all exceed 30-06’s penetration capability, whereas 5.56, 6.8spc, 6.5grendel, 7.62x39, and other intermediate rifle loads certainly do not.
Full power 30-06 is just a tad more powerful than 7.62nato/.308 (old milsurp is not full power).
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Of course none of this is even relevant. Civvies aren’t wearing armor, and regular police aren’t wearing rifle plates most of the time.
Don’t waste your breath arguing with anti’s either. They don’t know, they don’t want to know, and if they did know they still wouldn’t care.
They want to ban guns as a way to disempower their political opponents (you). Everything else is a post-hoc rationalization at best, and dishonest at worst.