Unless the humidity percentage stays at 70% or less -- plus that area keeps a basic same temperature 24/7, then you may havecontaminated powder and tainted 209 primers. I would start all over - fresh this year!

Another possibility is oil retention in the plug. The easiest way to correct that is be either storing the ML muzzle-up (or) keeping the plug out until you retrieve the ML for range or hunting work.

One last possibility is the firing pin on the door of the Omega action -- the little thingeee that gets struck by the hammer. Well.... that must be kept clean & oiled. Press both sides in when cleaning & oiling. There's also a low percentage-chance that it is KAPUT... uh broke!

Let us know how you make out!

One last mention......
For those without a dehumidifier & keep your powder & primers like this thread-starter did, put your powder and primers in the middle of a bag of charcoal briquets that you use for cooking outdoors. Make sure it's a non-charcoal bag so it won't get tampered with or tossed on a fire. Also keep it away from children & mark the bag with it's contents.

Keep the primers and powder surrounded by the charcoal - then fold the top of the bag with a nice straight line & put three clothespins on it to keep it sealed. That charcoal drives away moisture real well. I use it exposed during winter months at my summer home trailer. I spreadfour large cookie sheets in the trailer - each filled with exposed charcoal briquets.... ie... bedroom, kitchen, bathroomand TV-seating room.

Keep Your Powder Dry Folks
. . . . . . . Joe [/i]