My 470 is pretty light and I don't like shooting it from a bench at all.
I use the bonnet of my Landcruiser wagon and shoot from the drivers side. (Aus)
I cover the bonnet with a tarp so my elbows don't get burned on a hot day and use an old capok filled pillow doubled over as a rest.
I stand and lean onto the mudguard with my gut and lower chest touching it, rest my forend hand on the pillow and my elbows both down on the tarp.
With this set up I find I can hold as steady as if sitting at a bench but the recoil is much easier to take.
Also I don't need to carry around anything special as there is almost always a pillow, tarp and Toyota around my camps.