How deep can i seat the bullet?

I have a 300 Win Mag am starting to use bergers 185gr HPBT's i made a dummy case to check my COAL for This bullet and it turned out to be 3.61" it seems my chamber has too much freebore. these bullets like to be seated almost on the lands, but when i seat them to that they are barley in the neck of the case. anyone else have this issue? do i just have to use a heavier bullet?