This old veteran came into my collection recently and is the first one I've ever seen. The  Browning design influence is easy to see and it's extremely robust having been made entirely from ordinance steel with a great many hand operations obvious in the manufacture. Having zero prior experience with these I'm curious if it's normal for the next round in the magazine to extend partially into the receiver and rest against the lifter? At first this seemed like a guaranteed jam but actually doesn't cause any problem and I can't see any other way for it to function. No parts appear to be missing so I'm starting to think maybe it's supposed to work this way. Once in battery, the cartridge holder is depressed into its groove in the receiver wall by the bolt/slide assembly allowing the next round to spring partially out from the mag tube and rest against the forked end of the lifter. Inserting another round, pushes the lifter upward causing the protruding shell to go back into the magazine due to the camming action of the rounded front surfaces of the lifter and the new round slides right on in. That shell then becomes the one sticking part-way out. When the bolt/slide is drawn rearward far enough it allows the "waiting" shell to spring over the lifter into the receiver. The shell stop then catches the next round, holding it up until the bolt/slide is returned to battery depressing the shell stop and once again allowing the next round to start out of the mag tube. When looking up into the bottom port, the brass and a small portion of the hull is visible. This gun is capable of slam firing like older Ithaca 37s and it's not because of a disconnector problem, no disconnector...no problem!

edited for bad grammar

  I have one exactly like that and mine does the same thing. I don't take it out very often, as its quite a bit heavier than my other 12ga pump but its a great shotgun. Hope it helps...

Re the shell extending partially into the receiver:  That's just the way the Savage/Stevens shotguns are.  The more recent Model 30, 67, 69, & 77 function the same way (though they lack the slam-fire capability).   They use the shell lifter as part of the shell stop, along with a nub on the underside of the bolt carrier.  After futzing with more than a few Savage/Stevens pumps I know way more about their function than I'd like.....

Great info guys, THANKS for the help!