So I have a beater mossberg 500 with a field barrel I got in trade over 6 years ago. I did pull the action apart and give it a cleaning when I got it but never touched the magazine tube. I haven't shot it much since I got it, 2-3 informal rounds of skeet, and a sight in for a turkey hunt since then. I pulled it out today to go skeet shooting and the shells did not want to come out of the tube. They were not stuck, it was only pushing them out about 1/2 way, real sluggish. I pulled it all the way apart, barrel, bolt, magazine tube to works. I got all sorts of thick junk out of the magazine tube. Looked like gummed up WD40 or grease. After a little oil and reassembly she it running nice and smooth. All in all, you gotta keep em clean and oiled if you want em to work. I clean my rifles and handguns religiously after I shoot them, I'm not sure why I did not apply this philosophy to my shotgun.