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. Tested and approved by RedWolf. Best used on guns that shoot below 400fps.
Does this item include both the packing/bushing and the small, little thing besides the big packing?