Originally Posted by Gundy G
I understand using green gas causes you to get the most power from the rifle and too offset the power, heavier BB’s are needed
Yes propane will give you a higher FPS than duster gas. No you cannot "offset the power" by using heavier BB's. We measure gun limits by energy in joules (we just happen to chrony with 0.20g BB's and set the limits with that, because it's easier). Switching to a heavier BB's does not change the energy of the BB, just the velocity.