I asked, because I use targets stuffed with used plastic grocery bags, when using only target points. These are incredibly tough, yet even when shooting carbons from my Mathews compound, they can be pulled out with two fingers.
The bags last longer than whatever you’re covering them with.
For a deer, it would take a target about 15-18 inches deep, but thickness of the target will have little to no affect on arrow placement, unless it’s a shot from a treestand.
To be clear, I have not used the bags in anything but cardboard boxes, but see no reason someone as resourceful as yourself, couldn’t come up with a way to make them work.