These are the tools required to clean a Remington 870 shotgun. This type of shotgun does not need to be taken apart to be cleaned.
Step 1: Clean the Gun
Wipe down all parts of the gun using some paper towel or cloth, but this is less important to be lint-free. An old t-shirt works well.
Be sure to wipe down all parts of the gun especially the ejector area.
Step 2: Spray Down Solvent
Spray solvent, like M-Pro 7, on all possibly dirty components.
Spraying a lot of solvent is not a bad thing. You can never really use too much.
Step 3: Scrub the Solvent
Scrub the whole gun with a brush of some sort (a toothbrush works well). This works in the solvent and loosens up the buildup on the gun. Try to get into all the nooks and crannies.
Be sure to not use medal bristle brushes
Step 4: Wipe Off Solvent
Wipe the gun clean with a cloth, a clean old shirt or socks also work. Get everywhere you put the solvent and wipe it until it wipes clean.
Step 5: Clean Again
Wipe down the whole gun with a solvent-soaked the cloth again, and look again for any areas turning the cloth dark, and clean it.
Step 6: Cleaning With Pick
Use the pick to get off any thick chunks of carbon or powder buildup, or buildup in tight parts of the gun, mostly in the chamber.
Step 7: Clean the Barrel
Swab the barrel with a cloth soaked with solvent. Repeat with clean soaked cloths until a cloth comes out clean. Then swab it with an oil-soaked cloth, this coat of oil will protect your barrel from rusting.
Step 8: Lubricate the Gun
Oil all the components requiring lubrication. These are pictures of the 3 main parts of the gun that require lubrication.
Be sure to oil the rails for the bolt and the bolt itself.Try to keep oil away from the openings into the firing pin housing.
Step 9: Wipe Down
Wipe down the whole gun and remove all excess oil and remaining solvent.