I happened to ask my brother about the model 12, 20 gauge. He got when my Grandfather passed away. He said, I still have it, but I cut the barrel off at 18" for a home defence gun. I told him I have a Mossberg 500, 12 gauge, pistol grip, 8 shot tube. He can have for the 20 gauge. I now have my Grandfathers gun, but need to find a replacement barrel. Will any model 12, 20 gauge barrel fit. Gun is from the late 40's early 50's I think.