Remington is noted for being conservative. Be that as it may, 2800 fps with 140 gr.'er , out a 20" barrel might be zealous, ambitious, and maybe dangerous indeed. But 2700 fps maybe possible, looking at Hodgdons H4350 load data. Which is a max of 48 grs. at 49800 cup 2868 with Swift. Or a Hornady 139 gr with 50 grs. @ 47500 cup and 2906 fps. So, if you subtract 25-30 fps per inch of barrel length off a 24" inch . Each gun and barrel is it's own though, you may end up more or less.
JMHO, the 7-08 is likely the most practical factory round we have for deer. And a 140 gr. bullet, even at 26- 2700 fps, is more than needed for deer in most hunting situations.
Dave