I am having god awful experience with prop guns of all kinds

I am having awful experiences with prop guns; i’m getting little to no damage with an-m3, hispano, shvak, type 99 and mg151-20; while I see everyone absolutely blasting me and others with the guns AND belts I get only (lesser) white text with. Why do I have such experiences? Why are my cannons objectively dealing so much less damage than the rest of people? Of all these guns however ShVAKs provided me the most one click kills while with the others i need to make several pases up close to get at least a critical hit.