Arms Advocate put this out a couple months ago and I thought it might interest some of you. It's a fairly simple way to conceal a rifle, though obviously you'd want to think through any potential security or safety issues before using it. Let's hold to big boy rules here people; I'm sharing one take on hiding a rifle, not debating child access or local jurisdictional limitations on liability or legality.
This picture of the US flag was taken as a high resolution image from a Google search and uploaded to CanvasPop.com. It is 2.5" deep and there is an AR15 behind it.
Arms Advocate advises, "[I]t was relatively simple. One headache to avoid is realizing that no bracket will work unless it is sunken [sic] into the picture frame. Otherwise it will not sit flush against the wall and still be able to open without the picture hitting the back of the wall (which won't allow it to open)."
As you can see there is additional room on the wall for additional storage or mounting considerations -- an extra magazine, a flashlight, etc. The two black squares on the bottom are magnet brackets that will secure the bottom of the frame when it is swiveled down and "closed". The two brackets above are mounted into the frame using a 1 3/8" drill bit. Arms Advocate advises they are sunk 3/4" deep so that the frame can swing upward without hitting the wall but remains flush when closed.
Motion lights from Costco were added to the interior (seen here on right). This might be something I'd personally consider changing, as I wouldn't require illumination to put the weapon into service. Having the lights illuminate you while retrieving the rifle might not be desirable depending on why you were retrieving it, but I might not be thinking it through. Your thoughts?
Detail image of the 1 3/8" hole for the cabinet bracket. Arms Advocate advises, "[We] recommend drilling hole 1/4" or just slightly more from the edge. Not just for strength purposes, but when closed the 1/4" board used as backing will fit perfectly inside so picture is flush against the wall."
Here is a picture of the brackets and underside of the picture without rifle mounted, and another look at the final result below.