First thing you need is a good choke wrench. The Remington wrench has 4 notches and a square hole in the top that fits a 3/8" socket wrench. If that fits your choke, then prepare the choke by soaking it in penatrating oil, have someone firmly hold the gun, while you apply downward pressure to the wrench, so it doesn't slip and twist it out. If it doesn't break loose, try tapping the wrench with a mallot, and try again. Maybe try some heat. If that doesn't work, don't mangle it up, take it to a gunsmith. Mark