I have a thompson center omega with weathershield barrell and i finally got around to shooting this thing after it has sat in the gun safe for a year. I shot it 3 times and then took it back home and gave it a good cleaning. When i got it back out of the same to start my scope leveling process i pulled the breech plug out and looked down the barrel and it was rusted. So i took my cleaning kit again and used the brush and broke everything loose swabbed it and oiled it again. a couple weeks later (this being last night) went down and looked at it again and it was rusted again. Now when i oil the barrel i was just oiling a swab and running up and down it. Some one told me to hold it with the muzzle down and oil it until it runs out on the ground. Is this true or is there another way i can get the rust to stop coming back. Its more of a surface rust cause a couple passes with copper brush and its clear. Also i store it in a good gun safe with a moisture sitck. thanks for the help