Newbee here and I have a question about my 88. I bought a 20" cyl. bore barrel (gun came original with a 28" barrel) and when I went to install the 20" barrel it became very obvious it wasn't going to fit. The barrel screw was approx 6" from the magazine, thus I was unable to secure the barrel. Seems I need a longer magazine. My question: Will a longer magazine fix my problem or do I need to sell the 20" barrel? Also, can I even buy a longer magazine or will a 500 magazine work?