Am I wasting money by spending £30-40 in a set of fully adjustable sights for a 6" CP88, enjoyed plinking with it at 10 yards but recently found out it could knock down a beer can at 25 yards just aiming 1/4" above the can. started to ponder getting a fully adjustable rear sight and blade, laser is pointless at that range (D.T's) but love the open sights shooting. Adapt gun? or buy better? advice please!!