I’ve always said the most important difference between the AR 15 and AKM series of rifles is that the AR is for professionals, and the AK is for everyone else. Part of that professionalism is being capable, and willing to take proper care of your rifle. This includes basic cleaning, lubrication and the ability to recognize worn or damaged parts. The AR 15 is a very reliable rifle, but it runs best clean. It doesn’t matter if you have a high-end custom AR-15 build, or a mil-spec build using an 80 percent lower receiver.
Knowing how to clean an AR 15 starts at disassembly. Luckily, the weapon is very easy to take apart. The first thing you need to do in ensures the weapon is unloaded. Remove the magazine, and visually and physically inspect the chamber. The weapon uses two takedown pins, one located at the rear and the front of the lower receiver. Simply press these pins out of place. You can now separate the lower receiver from the upper receiver. Set the lower receiver to the side, and pull the charging handle from the upper receiver. This will pull the bolt carrier group from the weapon. Disassemble the bolt carrier, and set the pieces to the side. Now remove the buffer and buffer spring from the lower receiver. This is as far as you need to disassemble for a basic cleaning.
First start with the upper receiver. We are paying special attention to the inside of the barrel, also known as the bore. You’ll need a bore solvent, like Hoppes, and either a bore snake, or a rifle length cleaning rod with a bore brush attachment, or an eyelet. You’ll also need a number of bore patches. Coat the patches with solvent, and place them into the eyelet. Push it through the bore. Repeat the process, changing the patch as it gets dirty. Once the patches are coming out clean and dry, switch to the bore brush or bore snake.
Apply more solvent and run the bore cleaning device through a few times. Follow it with a few more dry patches to finish cleaning the gunk out.
The chamber on an AR can be tricky to clean, its somewhat small, and recessed. The first step is spraying some solvent into the chamber and letting it loosen the carbon. Next, attach a bore brush to your cleaning rods. Run the bore brush in and out of the chamber repeatedly. I follow up with a dry rag to remove any solvent and carbon mixture that remains.
The Bolt Carrier Group
Once the bolt carrier group is removed I suggest applying CLP, or any other form of cleaner, and wiping it down with a rag. Alternatively, Hoppes’ wet wipes are another excellent choice to wipe the bolt carrier, bolt, and firing pin with. The actual bolt can be rather dirty. I prefer to use a scraper or pick tool to get the large carbon buildup off. I then use copious amount of CLP on the bolt. I follow this with a gun cleaning AP brush and some hard scrubbing. I finish it with a rag wipe down.
Next, apply solvent to a rag, or use Hoppes wet wipe and clean the insides of the upper and lower receiver. Follow with a dry rag to ensure cleanliness. This is quite simple in the upper receiver. Ensure you clean the trigger area in the lower receiver as well.
Simply wipe down the buffer tube and spring with a solvent covered rag, and then dry. Not much to see here.
Once everything is clean, apply lubrication. I prefer CLP, because it cleans, lubricates and protects. I coat a clean rag with CLP and apply it to the insides of the weapon. I cover the bolt, the insides of the receivers, the buffer tube and apply a light layer to the outside of the weapon.
While your weapon is apart there are a number of quick checks you can do to ensure everything is kosher.
Take the bolt carrier group and physically ensure the gas key is tight. Apply slight pressure and check for any movement. The gas key should be completely stiff.
Take the bolt and check the lugs. They should be sharp, and smooth. They should not be smashed, dented, or broken in any way.
Take the bolt apart and remove extractor and spring. The spring should be strong, and the edge of the extractor should be nice and sharp, not flat or chipped.
Inspect the firing pin, it should be round at the end and smooth.
Reassemble bolt and bolt carrier group. Pull the bolt out of the carrier as far as possible. Set the bolt on the carrier on a flat surface. If the carrier slips downwards you need to replace the gas rings on the bolt.
Take the upper receiver and place a light source at the end of the barrel. Look through the barrel and inspect for rust and pitting of any kind.
Inspect the gas block for leaks. If it leaks, carbon will be built up around the block.
If any of your checks fail the test I suggest taking the weapon to a gunsmith for repairs.
If the weapon does not fail any of these tests begin to reassemble the weapon. Insert buffer and spring first. Next insert charging handle and bolt carrier group into the upper receiver. Set the upper receiver onto the lower receiver and reinsert the takedown pins.
Next, functions check the weapon. Ensure It is unloaded, pull the bolt back to rear and release. Pull the trigger with the weapon pointing in a safe direction. The hammer will fall. Keep the trigger held to the rear and pull the charging handle. Slowly release the trigger. You should hear a click as the weapon resets. The functions check is complete.
The cleaning process for an AR 15 is almost always the same. It could be a complete home build with an 80 percent lower, or a custom build with a side charging upper. The minor differences are just that, minor. The important pieces remain the same.