Here's a pic to help describe the types:
These are all .338 bullets. From the left, a 225 flat base with ULD ogive, bonded with .030 jacket. Next is a 250 flat base with the 6 tangent ogive, also bonded with the Mag Tip. This gives a good visual on the differences between the ogives. The ULD (which I believe is about a 14 caliber secant) on the 225 makes the nose noticably longer and sleeker and will have a BC advantage on an equal weight bullet. Its HP is slightly smaller than the Mag Tip as well.
And for comparison, there's a 300 ULD next followed by a 350 ULD. Both obviously with the ULD ogive and a RBBT but not bonded.