Before moving to E.WA, I hunted the salt marshes for 20+ years:
1. Never put your gun in a soft case to "clean later". If you don't feel like cleaning the gun right after hunting, dry it off; take off the barrel and put it aside to dry and then"clean later".
2. Never store your gun in a soft case; guns need to breathe or you'll get rust. If you don't have a safe; put your guns in a GunSock storage sleeve.
Barricade is an excellent product as is FroggLube; personally I found CorrosionX to be my own favorite.
www.shotgunworld.com has an excellent thread on the corrosion fighting abilities of these products and others. You will eliminate close to 90% of your problems by following those first two rules and near 100% if you use the mentioned lubricants on the exposed metal and on a final patch down the bore.