Buy some extended choke tubes. Then, set up your gun case so that you have to remove the choke(s) after your shoots, in order for the barrel to fit in the case. Then lube the choke threads with GI LSA oil, and get yourself a Tico Tool (hopefully a two-piece one) or a Boresnake and pull an oil (LSA) swab through the bore each time. Then wipe the exterior with one of your old t-shirts pretty much soaked in oil. You're ready for the next time.
Sounds like too much work, doesn't it. I do it to unwind after a shoot.
Bob Falfa