1. Cruel hat (begins with A or B)
2. A BSc rose (2 words, begins with B)
3. 3 sided figure exchanges gravity for note anyway (begins with C)
4. characters, we hear (begins with C or D)
5. Snake loses, argh! (begins with P, Q or R)
I've been trying to make bass core fit this - only because it's an anagram, and the clue looks as if it should be an anagram. If you google this, there are plenty of references to "bass core" but to an ignoramus like me, it doesn't mean anything. Perhaps someone else can make something of it.