I'm not having a pop OP but why has it taken you more than 5.5 yrs to ask? But there again that's your business I guess.
My answer to your question is to first ask a question by return insomuch as are you referring to playing from the fairway or the rough? I assume rough as any pitch from the fairway below 50 yds should finish inside the 3-5 ft mark. Although I would want to bin that 64 deg Weetabix you use and get a Cleveland equivalent.
The rough is a different fettle of kish however due to the variability of the lie both here and IRL. I work to a formulated chart and even then it still catches me out now and then. Nature of the beast I'm afraid.
All I can suggest is to practice as Jim advised but to jot down your results from as many different distances as possible so they can be repeated or revised as necessary. Once you have done this you will stand more chance of hitting the correct distances as quite clearly you aren't doing so atm.