Reply #42: You are quite right..."designed to" wouldn't be true of 5.56mm either... [View All]

[benEzra]

poor choice of words on my part. I should have said that all non-frangible rifle rounds (and all non-frangible pistol rounds) will go through interior walls, but all pistol rounds and most rifle rounds would be stopped by a hard exterior wall, and that 5.56mm/.223 has less wall penetrating ability than the older calibers. And as you state, wall penetrating ability just isn't really a design criterion for small- and intermediate-caliber rifles.