Down in Calvert County you just have to tell everyone within 150 yards of where you will be shooting.
I shot on an ex-GF's property (until one neighbor said it was too much) after asking the cops and one of the guys in my development, on his first Saturday in the new house put a clay thrower down by the pool and started dusting clays in his back yard (he was the only house on a cul-de-sac at that time, throwing the clays over a big gravel pit bordering on his back yard with a backstop of thick woods). The state cops told my other neighbor to pound sand after he called the local po-po multiple times then called the state cops a couple times until a trooper finally came out to look at the situation and the guy was found to be 200+ yards from any other house.
Go ask your local police/sheriff's office, there's a walk-up window for questions just like this.
Kharn