Hornady gets an extra 1.5gr of powder into the case beyond a max compressed load ? Sounds dangerous to me. The bullet length listed was already pretty long for a magazine and matches what is listed in Wikipedia. I note that the velocity listed by Hornady (2710fps 24" barrel) is lower than what you read in early (2007) magazine writeups but higher than the max load listed on Hodgdon website.

Also note that IMR 4350 allows 1gr more (41gr max compressed load) while still being lower in velocity. Must be slower. Perhaps the Hornady load is for IMR 4350 ?