Basic Maintenance for the Parts of the AR 15/M4 Series Weapon System

The AR15/M4 series weapons utilize a direct gas impingement system rather than a piston and are held to tight tolerances. This means unlike the AK-47 series rifles they must be kept clean and maintenanced more often. The gas piston on the AR-15 deposits considerable carbon and unburned powder into the action of the weapon which can build up ad cause malfunctions. Regular care can keep your AR15 running and prolong the life of some of the parts. The following parts are the most prone to fouling and thus require the most service.

As with all firearms first make sure the weapon is unloaded then again verify it is not loaded.

Barrel

The barrel on the AR15 should be cleaned using a quality solvent to remove any unburned powder and removing copper fouling that builds up over time. A standard cleaning rod with brush, patches and quality solvent are all that are needed to get the job done. Caution should be taken not to let ammonia based cleaner sit in a chrome lined barrel for long as it can start to “lift” the chrome plating from the carbon steel barrel. After brushing thoroughly run patches through the barrel from breech to muzzle until they come out clean. Finish by running a quality lubricant through to provide a protective layer against rust and to flush out any solvent that may remain in the rifling.

BCG

Disassemble the bolt carrier group and individually clean all parts. Carbon on the bolt and carrier may require a carbon scraping too remove excessive carbon build-up. There are cleaner available that assist in removing carbon from metal surfaces and if available can help speed up the job. Lubricate well and reassemble the BCG (make sure you reinstall the cam pin!) with a quality lubricant that does not attract power and create a muddy sludge in the action. Slip 2000 is the best choice for this process. Other lubricants will work also but nothing works better.

Upper Receiver

Clean the upper receiver thoroughly to remove any unburned powder and small pieces of casing or jacket material that accumulate. Lubricate any points where the BCG contacts the upper receiver. Do not forget to lube the charging handle. Again Slip 2000 is best but other quality synthetics will work also.

Lower Receiver

Cleaning out the lower receiver is easiest by flushing out with an aerosol powered gun cleaner. This allows for a thorough flush of the lower receiver without removing the trigger group. Lubricate with quality oil. See above for lubricant recommendation.

Recoil Spring/Buffer

Remove the recoil spring and buffer from the stock and lightly oil both then replace. Wipe the entire rifle down with a light coating of lubricant to protect against corrosion. Again Slip works best and will not damage the plastic parts of the weapon.

You cannot really over oil the AR-15/M4 weapon system. Any excess oil will blow itself out of the action as you begin firing. This may ruin clothing but will not hurt the rifle. Simple basic maintenance will help insure that your rifle or carbine functions correctly for when you need it.