The 240 Weatherby is a great caliber. The Nosler Partition 100gr is a great bullet, with the right shot placement, makes a great combo. Pending on what your shooting at, should be good to 500yds.
Depending on how you set up the sight-in, 500 yards will max out the Partition for deer size game and 1,000 ft/lbs. So, if you really are concerned about energy, use a good rangefinder or sneak in closer.
I use the .240 WBY for Coues deer so closer can be a real challenge. I've been using the Hornady 105 gr. AMAX until I run out since they were discontinued. I have been testing the Hornady 110gr. A-Tips now with good results and a little longer range and energy. If you're planning on larger deer size game, whitetail or Mule deer, I'd run the A-Tips. This might require an adjustment to the chamber dimensions.
Love the 240 Weatherby
I usually shoot the 95 grain ballistic tips but if I was stretching it out to 500 then I would use the 105 Berger VLD hunting. It shot very well in my rifle with H4831 and RL22.