There are several types of boattails.
1. standard cup and core bullets where the lead section extends into the boattail section of the bullet

2. same except the lead does not extend into the boattail section

3. bonded bullets with boat tails

4. Tsx and TTSX style.....again no lead in the rear section.

#1 is the only boattails I do not buy as there seems to be a real increase in separation of the lead core from the jacket.

As time goes on it seems I find myself shooting more Accubonds than anything....very high BC and they do not separate......superb accuracy too.