JR 137
Grandmaster
If I’m not mistaken, the AR-15 can shoot 2 different bullets. I think NATO issue (which is the rifle I was referring to) can shot both, whereas other variants can’t.The standard ar15 and simular fifles are 5.56mm, which is functionally a .223 Remington. If I remember right, 5.56 is loaded a smidge lower pressure and the brass is a tad thinner. However, depending on how tight the tolorace of the chamber and throat, they both fire and cycle well to fine in each other. The 5.56 does better in .223 tham vice versa.
Either way, it was pretty loud.