Toughest? It'll shoot, extract and eject modern 1 oz. loads; loads that give my old pumps hell, for instance Herter's game loads that I wouldn't dare shoot in my English boxlocks. Steel heads replacing brass heads have caused problems with many older repeater guns and for that matter, some fairly modern, in extracting and ejecting. Last week while shooting snipe with a 1959 M12 16 shooting the same shells, I'd get one shot and then with both hands to force the slide downward to extract and eject which hasn't happened with other ammo. I have a modern 870 12 that gags on RGL but shoots Winchester promos fine. Snipe are at the top of the list of gamebirds for the table IMO--milder than dove with a layer of white fat between skin and meat. Cook them rare to medium rare; overcooked, you might as well have cow liver on a stick. Same with woodcock. Here's some snipe I plucked and cleaned a few years ago: