The 1-2 gr extra case capacity, 2" of barrel, and 0.007" bore size aren't going to equal 200 ft/sec. Both have SAAMI of 65k psi.

Example:

280 AI (26" brl) 160 gr 3 loads ~ 3040 ft/sec
270 Win (24" brl), 160 gr, 2825 ft/sec

280 AI, 150 gr, 2 loads at or pushing 3100
270, 150 gr, 3 loads at or slightly above 2900

Hodgdon tells a completely different story.

Adversity doesn't build character, it reveals it.