Oh screw that. Now I wouldn't have a problem with neighbors but if I came and questioned them and they cussed me or were the least bit rude it would be on. I'd say fine, go get my 22 and a few pistols, bring lots of amo and proceed to fire off my entire arsenal at a uncomfortably close range. If required I'll bring out the 7 rem mag and sight that in. That gun shot is worth a thousand words. They will leave at the crack of a high powered rifle. If nothing else they will think you are crazy and will not come back. Maybe a urban legend will be built around you. Be the crazy guy.
My rifle range is right in between the 2 ponds. It gets regular use, in cold months by me, in warm months by my wife's sheriff's deputy nephew. I think the two reasons we don't have anyone coming onto our property anymore are 1) somebody's home most of the time and 2) I'm the neighborhood crazy guy.