The long and short of it is I bought an old, used Moss 500 for $250. Not the greatest bargain, but it had wood furniture when a new one with synthetic furnishings was $350. (I live in NJ.) It was a while before I got it to the range, after spending nearly a 4 hours cleaning it from tip to tip (the previous owner clearly was not as anal about maintenance as I am.) I get it to the range, start to thumb in some rounds, and find that its been capped.
I get home, and after some reading I realize its just the wooden dowel in the mag tube. (Didn't even think of that at first.) The dowel was broken, so getting it out of the tube was a project, during which I dented the tube. After four days, a lot of solvent, and a lot of doubting my own physical strength, I get the magazine tube off.
This is where it starts to really get interesting. This Mossy has a "G" prefix on the serial. According to
this article, that means that I'm going to have to replace the entire action assembly. Except when I measure, its the 7.75" length of a more modern action. This has turned into a project gun, simply to make it look and feel brand new. I'm already replacing the magazine tube/spring/follower. I come here to ask if I need to replace my entire action tube/fore-end too, or if the 7.75" will work on a new manufacture 5-shot tube.
Sorry for the "long" more than "short". I like providing detail for this stuff.