If your hop-up adjustment is not having a big effect on the hop-up of your BBs, then it probably means that your hop-up packing is worn down and is not gripping the BB properly before it is fired out.
A new hop-up packing will allow more accurate hop-up adjustments. Best used on guns that shoot below 120/ms If your gun shoots above 120m/s, then opt for the HARD TYPE hop-up packing instead. Especially recommend to use this hard type hop-up packing onto upgraded AEG as well for improving full auto mode shooting effectively.