I recently purchased a nice 1979 marlin 39-A. After shooting it some I noticed that I was having some issues with the rounds feeding into the barrel. It was worse with .22 shorts than .22 long rifle. I also noticed that every once in a while the lever will lock in the open position and will not close until I pull the magazine and dump the shells. I replaced the cartridge guide spring and now the shells feed like butter into the chamber (shorts and long rifle). However, the lever locking issue still occurs occasionally, again...it seems to happen more often with shorts, especially when I load 20 or so. I’m wondering if I need to install a new magazine / cartridge cutoff spring? Suggestions??

i don't have an answer for you but if no one here has it then i suggest you go over to rimfirecentral to the marlin forum and ask there. a member there, gizzy, knows more on these rifles than just about anyone.

Thanks!

Have you tried cleaning the magazine tube and the plunger that pushes the shells into the action.
Have a great day.
Jim

Just curious if you resolve the issue?