GOD EATER 2 RAGE BURST: Blast Cannon Recipes 

You can create these when you get Blood Bullets. Once you use a gun enough it levels up and you gain new chip modifiers, lvl 9 is the max. So fairly early on yes.

Oh that is nice because I need the anti gravity chip

+Najee MacNeil Anti-Grav is the lvl 9 chip for the blast cannon :)

By now I think he should already have figured out. But just for the correction purposes, it's actually Blood Bullet Level 6, not 9.