If you are practicing that often, and I'll assume your bow is tuned ... it's probably your form and aiming techniques that need to be refined.
Like someone else said,
Practice doesn't make perfect - Perfect practice makes perfect!!!
Ever take a lesson? Know someone who consistently shoots real well who could watch you shoot?
I'd suggest going to a local archery shoot, now this part is IMPORTANT .. notice who the "real" good shooters are, then ask if they wouldn't mind helping a guy with a few suggestions. Beware the guys who throw advice around but never step up to the line ....
I haven't met a serious archer yet who won't gladly give advice on how someone can improve their shooting.