The main cause of projectile vomit is pyloric stenosis or gastroenteritis. You may want to get your baby checked out for both. My little boy had sometimes projectiled when he was very young. To be safe we winded up getting him looked at for these things. It doesn't hurt just to make sure your baby is okay and nothing serious. Our pediatrician recommended we do it too. It could be other things as well. Definitely run it by your doctor!
It sounds like what my son was like and he was diagnosed with CMPA (had lots of other symptoms). But to begin with he did similar behaviour to this. His poos became explosive though with mucus. It's hard to tell because they're all so different even with the cmpa symptoms. Could be lactose sensitivity too.