The other reason it happens is not having the butt placed firmly against your shoulder. If you have the butt planted well, your hand won't be doing much anyway. Like most of shooting, it's all boils down to operator error.
I agree. Also, letting the shoulder collapse under recoil will break your grip on the hand of the stock.
Beyond that, it's whatever works for the individual shooter I suppose, and it's interesting to read other guy's methods. To me, it would seem that trying to grip the gun well behind the guard only provides running room for the smack to the second finger to really hurt. With either straight or pistol grip double guns I rest the knuckle of the second finger against the back of the guard bow and grip with something on the order of a normal handshake, never really tight. With double shotguns and double rifles up to .577 Nitro, I've never had the slightest discomfort to my second finger.
