Rust on a Remington 870

[RustyJr]

I was wondering if anyone else out there with a Remington 870 Express has any issues with rust on the receiver and barrel. I have a 3.5" 12 gauge that I have had for about 4 years. When I first got it I put it behind the seat of the truck in a case and left the case unzipped so that it could breathe. At the end of the day (only eight hours or so) I removed the shotgun from my truck and took it inside. I immediately noticed that it had rust on it. I also had a Remington 700 in 223 that experienced the same issue (roughly the same amount of time in the truck). I have done this with other firearms for a lot longer and never had an issue. I understand that guns can rust but these seem to rust a little easier than most. I just purchased a brand new 870 Tactical and after getting it home noticed what appears to be a small amount of surface rust on the mag tube just below the action bars. I have since rubbed it down with Rem Oil (same thing I used on my other 870 after having rust issues with it).  Has anyone had any issues similar to this and also what do you use to prevent rust?


 
   Thanks,
          RustyJr.

[hillbill]

just keep it well oiled, not dripping but a good wipedown with a oily rag when yu put it in the case.salt from your hands and humidity is prob doing what your talking about.some of the rems had a matte finish that would rust on a cloudy day if not oiled.everybody has a favorite oil but i dont.ive used everything from motor oil to dextron to bore butter and lots of the commercial gun oils.lucas gun oil does work well for me for long term storage.short story is, if its oily it wont rust.some type of finishes tend to rust worse than others.

[Goldstar225]

A parkerized finish is very porous and needs a good dose of oil to seep into the pores to protect the metal.  I'm experimenting right now with Bioshield T-9 on my refinished Remington 870 that I carry on duty.  After letting a good coat of oil soak in I coated the gun with T-9.  It's been about 8 months now and no sign of rust. This is a gun that lives in a patrol car, gets deployed in the rain and waits till the end of shift for a wipe down and gets handled by sweaty hands. 
 
Bioshield T-9 is sold to prevent rust on table saws, drill presses etc..  After application the solvents evaporate off leaving a waxy residue to seal the metal and protect from rust.  I believe that the residue will effectively seal the pores on parkerizing, trapping the oil in and keeping water and sweat out.  So far it's looking good but I won't be confident until a couple more years pass. 

[Bugflipper]

I also use the bioshield t-9 on a benelli m4 duty shotgun. It works well. We qualify every 6 months, so it gets reapplied then. I had a 870 express as a duck gun years ago. Coated heavy with oil it would still get a surface rust if it wasn't re-oiled after drying from hunting in the rain. I ended up removing the rust with hydrolysis and painted it. When it was sold I stripped the paint and it looked like new.

[Harry Snippe]

I kept giving the gun a few layers of cold blue .That seemed to seal the metal enough that an oily rag at the end of the day as with the other guns saved the day .

[SHOOTALL]

I don't believe the finish is parkerising . I have a 870 that is and it is green/gray in color it has been to the bottom of beaver ponds and rained on many times . It has a chrome bore and afer 25 + years still has no rust. I believe the Black finish is a phospate finish and not as protective . I have seen alot of police trade ins with the black finish and they are brown from rust but once oiled seemed to be fine. There are better oils or coatings to protect the finish . I have a camo gun like mentioned and where the camo is worn off it rust also. Lets face it the express guns arte built to be cost effective so they don't have the best finishes. Make sure all sweat and moisture are off before coating with oil or it will be trapped under and still cause rust.