I crono-ed some rds in my 16" Noveske rifle yesterday. It was approx. 30 deg and sunny. I was shocked to see how fast the HSM 5.56- (version of the Hornady T2) 75 grainers.
7 rds- 2743, 2698, 2760, 2780 and 2736, 2704, 2690
I know they are all over the place, as they were on target also. This stuff is fast but it groups around 3-4 moa in my Noveske. I did not have any Hor. 5.56 to compare it to. But my crono works well, we tested some various other handloads that I am 100% sure of the fps and verified it was on.
24.6 grains of TAC- 77 Noslers with LC brass- CCI primers= 2620 average out of the same rifle and groups right at 1 moa with 5 rd groups. This load is a good bit over max but it is fine in my rifle.