Good gun care is usually centered around keeping rust from developing on exposed metal parts. Rust on external metal surfaces is ruthless with uncoated shotguns, especially those used in saltwater environments. Thoroughly cleaning your choke and shotgun after each hunt good practice, but often uncleaned firearms using modern ammunition are better left dirty for short periods of time unused as the grime can create a thin protective layer to prevent rust formation.
Choke Tube Maintenance
Fixed choke tubes require little maintenance other than routine inspection to make sure there aren’t any dents, gouges, or bulges that would affect its performance. Since fixed chokes are part of the barrel itself, it is more susceptible to damage from being slammed into objects or being used as a rest when not in use.
Choke tubes that are a part of interchangeable choke systems should be inspected regularly with focus given to the threads which secure it to the barrel. These threads can become rusted if water sits for too long which results in a stuck choke tube. Place a few drops of gun cleaning oil on the threads of the choke tube and do not overtighten.
General Shotgun Maintenance and Cleaning
Shotguns and choke tubes can be cleaned relatively quickly and easily with just a few tools. The basic equipment needed for gun care are 3/0 steel wool for rust removal, cotton cleaning patches usually in various sizes, a stiff jointed cleaning rod with a swivel tip for each gauge type, solvent such as Hoppes #9 or acetone, an oil wiping rag, gun grease, and paste wax.
Thin-walled shotgun barrels should be examined regularly for dents or bulges. If irregularities are observed, the gun should be taken to a gunsmith who has the correct tools to either raise dents or smooth out bulges. If a fixed gauge shotgun has a bulge in the choke, it is usually easier to trim the barrel enough for it to be re-choked.
Occasionally the muzzle of a shotgun will become obstructed by mud, clay, or snow. After unloading the gun, the muzzle should be cleared with a stick or tool that will not damage the barrel or choke. Under no circumstances should an obstruction be shot out of a barrel.
Shotguns tend to develop streaks of plastic wad, unburnt powder, and shot debris in the barrel after many hundreds of rounds are fired. This tends to occur just after the chamber or near the muzzle of the gun. Remove this buildup of debris in the barrel by wrapping a wad of fine steel wool around the cleaning patch of the cleaning rod and work the bore thoroughly to smooth it out.
The chamber and action can be cleaned with a bristle brush soaked with solvent. Cleaning wipes can be used to absorb any excess solvent or gun powder residue. The outside of the gun can be wiped with a silicone-based cloth with a small bit of gun oil. In areas with very humid conditions, heavy gun grease is the protectant from rust development.
Oil should never be squirted at random into the action of any shotgun. Excess gun oil attracts dirt and dust that could cause problems with the gun cycling. For shotguns used at temperatures near or subzero, flush them with gasoline and then lubricate with powdered graphite.
When hunting in wet weather, take the time before hand to apply paste wax and then polish it off after it dries. This will wick water away from the exposed parts under heavy rainfall. For shotguns that have been soaked or have water internally, either completely disassemble the gun or let it hang with the muzzle downward near a source of heat so that it can dry out. Once dry, apply oil liberally to prevent rust from forming.