Is there a natural difference in accuracy between round nose bullets and spire points?
I have seen much less meat destruction and bulletseparation
in roedeer shot with 150 gr.round nose bullets in 30-06 than with the 150 gr.spirepoints I have used till now.(both reloads with similar measured speed)

Is there also an advantage of boat tails over flat based bullets for distances up to 200 yards?

IMO there's no difference in accuracy due to the shape.....(round nose VS spire point)...there might be in a particular gun but that is an anomoly to that combination.

RE: boattails up to 200 yards.....IMO they are a disadvantage. They offer a slight tradjectory advantage past 400 yards but they certainly are not more accurate and they have a tendency to shed the core in conventional bullets more often than flat base bullets.

Well, yes and no. Inherently, the accuracy potential of the two designs are very similar, and any decent hunting bullet should be capable of accuracy in the 0.3 MOA range.

That said, it is very common for round noses to out-shoot spire points. Due to their shape, the round noses often are closer to the lands, for one. They seem less sensitive to seating depth in general.

As far ballistic efficiency, certainly on something as small as roedeer, it would matter none. If round noses work better in your rifle, and they do a better job on game for you, I can see no draw back, at all. JMO, Dutch.