Vel'koz ult on Braum shield?

My boyfriend and I were playing and he was playing Braum against Vel'koz support. So we're running from them and he throws his shield up as Vel ult'd us and his shield didn't block it? I just wanted to know if that's a bug or because it's a channeled ult. I'm not confident on how Braum works, but I felt pretty sure it should block that considering it's a projectile... or is it? Anyways, not sure and need to know.