The "ballistic" advantage of a boat tail isnt really realized till you get out to longer distances like 300+. "after" that, they slow down at a lower rate than round nose.
BUT, a shooter should try boat tailed bullets as a matter of course to find the most accurate load. If your particular rifle shoots boat tailed bullets better than the round nose bullets, then shoot them.
Typically I have found flat based bullets "easier" to find a top performing load.
For those who are interested, I have found Winchester 760, and H414 to be great powders for top performance in my .303's. (175-180grain bullets).
Have fun you gunnutz!