While we're on the topic of doubling...I have a 10ga SxS, it weighs around 12lbs. I was doing some load development one day during goose season last fall, working up some 2 1/4oz turkey loads, and having been out that morning I had oiled up my gun when I got home. Turns out that there's a great path for oil to flow down around the trigger guard and onto the grip somewhere in the lock work. The grip got slicked up by the oil, and I didn't really notice until under the recoil of the first shot, the gun slid rearwards out of my grip having imparted enough momentum to my hand for my trigger finger to slip back and hit the rear trigger. That's the first time in my life that I've ever found my muzzles pointing up 45 degrees after a shot. It must have been fast enough to, my chrony survived.
