"You have to be in the right place and the right time."
20 acres??? It might be more advantageous for you to invite a few more hunters to hunt the place besides yourself; in order to help move the deer around more.
In order for you to stop from getting a bruised shoulder:Try to keep the shotgun buttstock deep in your shoulder pocket. Mount the shotgun by bringing it to your head, and not by bringing your head to the shotgun. Also mount the shotgun...by bringing the buttstock slightly forward of the shoulder pocket and then bring the shotgun straight back, along with a good cheek weld and your shooting eye aligned with the sights. Wear a heavy hunting shirt, or a recoil shoulder pad when practicing with your shotgun. Sometimes I stuff rags in front of my shoulder pocket, under my shirt.
I don't like to stand hunt in the bottom lands too much...because of the tendency for the wind to swirl around in different directions.
If you pick-up a flinch...work it out by going back to a 22 rimfire.