It has been my personal experience that with my 16" converted AR the supersonic vs subsonic loads make the most difference. What I mean by "most" is the genuine need to resight the rifle. I've pushed . . for instance . . . 150gr bullets subsonic and supersonic. The difference in point of impact was significantly greater doing that than shooting 150gr bullets (at the same speed) at 100 and 200.

I know that is not exactly what you asked, but dang. Here, this will probably serve way better than any words I can cobble together (because there are soooooo many potential variables):

https://www.google.com/search?q=300b...oCoCg#imgdii=_