I also lost a grouse this year from a 20 foot shot from a branch. It fell into steep, very rooty undergrowth. We looked for an hour, digging beside root hollows, using the machete to clear branches, moving dead wood etc., no luck! We could not believe it. Found a 5 point elk shed from last year in the process. We haven't lost one since. Speed is the key.....get to the grouse instantly. I assumed that from the head shot and a fall straight down that I could do like you, put the safety on, put the 22 in the truck and pick up the grouse......never again. Shoot and run to the spot as quick as safely possible and if this is not possible, I will not shoot. This was my first year hunting grouse and boy did I learn more than I thought possible.