A 240gr bullet with an impact velocity of 1150-1200fps will absolutely kill a deer, and do it well. I mean, with something like an XTP we're still looking at full expansion and about 24" or so of penetration at those velocities. That will still do way more tissue damage than a non-expanding SWC, and few here would argue against the well-known effectiveness of such bullets.
Now, it does help if you handload, because not many factory loads will push a 240grHP to 1800fps out of a rifle barrel. Though, Buffalo Bore has a 240gr HP load that runs ~1900fps from a rifle, appropriately named the "Deer Grenade." At 200 yards it's still moving along at over 1250fps and if a typical hunting load at handgun velocities can anchor a deer at 50 yards, this load will do it at 200.
