Sound control for home range

[august west]

I live in a semi-rural sort of area but we have some subdivisions within easy earshot. I could easily shoot around 100 - 150 yards on my land but I've been thinking about noise control for our big artillery pieces. Has anyone ever come up with a sort of portable "silencer" that could be used to muffle shooting noise? I'm kind of thinking about something light like a plastic garbage can - the bottom cut out and lined with acoustic eggshell foam. Set it up on a support so that the muzzle is inside the can area.

Weird idea? Waste of time? Should I just buy a ranch in Montana?