How to Lubricate an AR
Lubrication is critical to proper function and longevity of the components of an AR. You should lubricate an AR at least every time you clean it (and then some).
AR Lubrication Myths
MYTH: I can use WD-40, motor oil, grease, Astroglide, etc. to lubricate an AR.
No. Use a fit-for-purpose firearm lubricant. Period.
As explained in the Clean and Inspect article, the right lubricant (e.g. CLP) makes cleanup so easy, you barely even need cleaning tools (a simple wipe is sufficient in most places). Do yourself a favor and use a good firearm lubricant.
WD-40 is not a lubricant (it is a water displacer).
Motor oil belongs in a motor; too thick for firearms.
Grease belongs in bearings and on heavy machinery; it is way to thick for your AR. It will only get thicker as the temperature drops (leading to cycling issues) and it will attract and hold grit, which will cause abnormal wear.
MYTH: My BCG has a [fill in the blank] coating, so I don’t need to lubricate it.
While that may technically be true and even stated by the manufacturer for certain coatings (e.g. DLC), lubrication is still strongly advised and it certainly won’t hurt. It is also likely that some associated parts are not coated by the coating in question (e.g. the bolt), and these should still be lubricated.
MYTH: I can overlubricate an AR.
While the definition of “overlubricate” is subjective, there are certainly best practices.
First and foremost, you should avoid getting a significant amount of lubricant in the path of hot gas (barrel > gas port > gas block > gas tube > gas key > bolt/bolt barrier) at all costs. Lubricant of any type will burn and carbonize under the extreme temperatures experienced along this path, which will do just the opposite of lubrication.
Excessive lubricant can be an attractant for dust, dirt, and grit. While better than under-lubricating, overlubricating an AR will lead to more frequent cleaning.
That said, we have run ARs “dripping wet” with CLP and the only issue was oil spatter on our shooting mat and oil oozing out of the gun.
Lubrication Tools and Materials
Lubrication Process
JAD: Just A Drop; apply using a needle bottle
LF: Light Film; apply with a wipe or finger
DBS: Don’t Be Stingy; apply liberally
Lower Receiver:
- Pivot/Takedown Pins
- Shaft (LF)
- Channel (JAD)
- Magazine Catch (JAD)
- Bolt Catch (JAD)
- Hammer/Trigger Pins (JAD)
- Buffer Spring (LF)
Upper Receiver:
- Upper Receiver1 (TF)
- Barrel Bore2 (TF)
- Forward Assist (JAD)
- Ejection Port Dust Cover Pin (JAD)
- Charging Handle
- Inside of Shaft (LF)
- Outside of Shaft (LF)
- Pins (JAD)
- Bolt Carrier Group:
- Carrier Rails (DBS)
- Bolt Lugs (DBS)
- Bolt Exterior (DBS)
- Gas Rings (TF)
- Firing Pin (TF)
- Extractor Pin (TF)
- Cam Pin (DBS)
- Ejector Pin (JAD)
- Cam Pin (DBS)
1: We apply a thin film to the inside of the upper receiver (i.e. where the BCG and charging handle slide). This ensures adequate lubrication of the BCG and charging handle, and aids in cleanup.
2: If you will be storing your gun (i.e. not firing it immediately), we recommend that you run a patch saturated with CLP (NOT bore cleaner) down the bore. This will prevent corrosion of the bore. Before you fire the gun, run a dry patch down the bore to remove the CLP protectant.