A Bajrang gun, I think, is the size of Loki's tooth in Zoan form, a blow like that doesn't even tickle.
Oda saw that most readers thought the giants were always weak and didn't have much relevance, and put the combined strength of all the giants into Loki.
I feel sorry for Gunko and the other holy knights, they're going to be skinned alive.
Now I understand why Big Mom was afraid to go to Elbaf.