Long range shooting - the myth of 5.56

Some guys in the comments referred to the idea of the ineffectiveness of 5.56 at long ranges as a myth. I understand the argument that it's just as effective as 7.62x39 and 7.62x54r at those ranges. But they are not that effective at all lmao. I'm like 99% sure that 6.5 grendel or even the 6.8 spc would have much better performance over 500m than a 5.56.<br><br>Also side note, does anyone here know of a reputable company that makes decent (not match grade) grendel ammo at a reasonable price?<br><br>&#x200B;