Magazine Cap Issue.

[Quarto]

Hi folks. Recently my Stevens 320 has developed a gap between where the magazine cap stops screwing and the ring that is welded on the bottom of the barrel that slides over the magazine tube.
I have a feeling that it is a issue with the magazine cap because it doesn't even go down enough anymore to reach the locking pin and the magazine tube looks normal near the threaded end.
I've attached a few photos and perhaps someone can tell me what causes this and how it can be fixed.

Thank you.

[bombadillo]

Bring it over to my place and we can see if a strap wrench will butt it down some more. It may just need a little love and some lube.

[Quarto]

Sounds good. I should pick one of those up but i keep forgetting about it. I tried using a rag and vice grips to no effect.

[Quarto]

Put a good amount of hoppes 9 lube on the cap and it helped a lot.

[kentactic]

is the center of that cap a seperate peice like it is on an extension tube? I ask because if the threaded center peice is to deep it wont allow the locking nut to tighten down all the way. If your using tools and lube to get it right somethings wrong.

[Quarto]

No its one piece besides the sling swivel in the center of it.

[bombadillo]

Seriously, gimme a call sometime tonight and we can check it out. I'm hoping its not somehow cross threaded or something like that. I'm free pretty much all evening and can give you a hand if you want.