ive been very lean doing bi injections if your like me and a beleiver that theirs a beneficial side to spot injection, you know u MUST go deep, your not even near the fascia 1/2" in, but ya ur in the muscle, the thing is ur putting a oil pocket so close to the surface of skin it "SHOULD" leak out a bit.. this is what ive noticed from experience, burying it or not. just flex ur bi after a 1/2" inj it should leak...i knwo it sucks but try to go deep as possible every inj i burry a 1.5" in shoulders and 1.5 in biceps now, get really deep if u hit too hard tissue possibly bone back it up slighly...