I would try the 150 Grain Barnes TSX boattail it has an incredible .529 BC and will shoot as flat as any 140 Grain due the high BC. Itwill have far less wind drift, and will have highest retained energy downrange. You may want to plot the velocities and BC of a bullet vs the 150 TSX in the link below to quantify results.

http://www.biggameinfo.com/BalCalc.aspx