mike siegmund
Copper BB
What does the screw in the magazine on a mossburg 42 c do?
don't know why but I cannot scroll downI might be wrong but from what I read here it's to adjust follower spring. Here's the link.
https://www.rifleman.org.uk/Mossberg_42MB.html
Scroll down to schsmatic.
Ok that's what I thought it was LOL but "adapter" screw threw me off I thought it might be a adapter for different stock fittings ok thank you and ya I have two mags one with a screw one without and it looks like finding one for it will be impossible so I at least have oneAre you talking about the screw in short adapter R-120? It is to allow you to shot shorts in your rifle. Do not loose or you may never find another. Interestingly I bought a model 42 (don't remmeber which letter) for a good price as the fellow said he could not get it to load. I didn't realize what the problem was until it arrived in the mail (Canada eh). I think it was the first short adapter I ever saw.
Mine is cracked a very common problem. Sarco parts shows a 42 stock and I am giving it a try should be here soon I am hoping I can use it. If not its accu glass and hope it looks good after as mine has not one but three cracks one being pretty bad the other two finish cracks. On a side note it was missing mag guard so that will give it some strength as well. Not a great design but fixable good luck with yours.I forgot to ask how is your stock? The only 42C I found so far had a cracked stock. The other problems were an ugly cut out for a peep sight (42C had no peep or cut out for one and no sling swivels) and had holes for swivel screws. Now I am looking for an unmolested stock. Not much to choose from here in Canada.