My father-in-law has a 30-30, 30-06, and a .22 rifle that he owns but hasn't shot in probably over 40 years. He only has full use of one arm (though it's a quite burly arm). I wanted to take him to the range this weekend to shoot his guns. Should he have any problems shooting them while seated? I haven't shot any rifles extensively, so I don't have enough experience myself to say. Thinking just now, I guess he would need something to prop them on. Provided we don't have a bi-pod or anything of the sort, what's a good alternative?