I have an old Winchester model 100 that I use for deer hunting. It been passed down through the family and is in immaculate condition. Looks brand new. I take care of the gun and always clean and oil after use. It's stored in my safe with the rest of my guns. Here's the thing even when it's clean and well oiled if it sits for awhile the bolt jams and will not open. Once I knock it open its start working fine again. Guns works flawless until it sits for awhile. Any suggestions or ideas? Thanks.