Brownells Gun Techs Steve Ostrem and Caleb Savant are back to help us separate fact from fiction. Or should we say “friction”? Today’s topic is the PROPER way to lubricate an AR-15 bolt / carrier assembly. Turns out the Army Way isn’t always right. When our guys were in basic training (a few years apart), what the Army told them to do was wrong. Well, Steve has theory that it served a purpose, but keeping the rifle running reliably wasn’t it. Caleb shows us the metal-on-metal friction points where you actually need oil: the rails on the underside of the carrier, shiny wear points on top, and just a dab on the cam pin. How much oil should you use? The AR-15 is pretty forgiving on that point. Just keep it out of the combustion areas. Those little holes in the carrier are gas vent holes, NOT oil holes! Do BCGs with special coatings like Titanium Nitride or NP3 need to be lubed? The guys have some advice on that. What are your tips for lubricating an AR’s BCG? Tell us in the comments below.
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When I was in the Corps (99-03) they would tell us to leave a light coat of CLP over the whole surface of each part. We’d just use our CLP brush to distribute the CLP evenly throughout the BCG. Till this day it’s hard to break that habit and I haven’t had an issue so far but then again I’m not kicking doors down with my AR anymore.
So putting some oil on the bolt itself is unnecessary too?
I use franks red hot…I put that shit on evrything…
what about some lube on the lugs?
I use Tri-Flow Lubricant on my Friction surfaces. I find that is works very well on both rifles and Handguns.
i hope some day a bat shit crazy rich guy builds a functioning gun that is the size of a bulding
Does the actual bolt itself need any lubrication?
I run my AR's wet. The army did a study where they pitted un lubed guns against run wet guns in the desert and found that un lubed guns failed to fire long before those run well lubricated. I read this in the military times I think in 2008. At any rate the one time I had to shoot my M4 in Afghanistan it did not fail me by keeping it maintained this way.
I tried a little something that seemed to help the gritty feeling of a new build copper anti seize (not much) just a dusting on the inside of the upper where the bcg makes contact enough you can see the copper residue , then oil ,grease of your choice also another very light dusting of the spring I can’t tell you how much of a difference it made
All that oil on the bottom drips into your mag.
Lately I've been mixing Crisco with Country Crock.
You lube it where the TM -10 tells you to lube it.
In short: generous lube on the gas rings, locking lugs, rails, and bolt. Light lube everywhere else.
I lubricate my BCG with high temp wheel bearing grease. Or any lithium based grease. I just put a dab on my finger and put a light coat on those friction points they mentioned. Not a glob or insane amount. I do put some around the bolt as well and the cam pin. Baby runs smooth as silk. Stuff is pretty cheap and will last a loooong time.
Just based on past experience, military and otherwise. Any semi auto/auto weapon that uses gas blowback, oil + powder = gunk. I agree with the points you show to be lubed. Have had better luck with drying graphite or in a pinch, a #2 pencil, rather than oil. Especially in the great white north. Wipe every moving part completely dry. In desert settings, experience is that sand sticks to oil. Welcome comments!
I built my first ar haven’t even fired it jus dry firing a little bit and I noticed the bottom of my bcg has a terrible wear mark on the front bottom part almost like it’s grinding against the hammer when it slides back, what does this mean? I keep my guns well lubed too
John at warrior poet would be so mad
Hickok45 said to put oil in those 2 vent holes (in his AR-15 cleaning video from 2012). That's what I've been doing myself, but this video convinced me otherwise. Thanks for the info guys!
I never served, but I had also learned SOMEWHERE to put a drop in the gas key and into the holes on the side of the carrier. It was very important. I had also learned that the bottom surface should be dry. Then, everything else should be dry except the friction surfaces on the top and bottom – lubing up the carrier and the bolt itself and all that was a bad thing that would be a dirt/carbon magnet.
So good to know that 2/3rds of everything I've learned is wrong…like usual. =)
My lubrication process…
Step one: Grab the BCG and lube.
Step two: Apply to all surfaces inside and out until a steady stream is falling to the ground.
Step three: Give her a shaky shake.
Step four: Do the same to everything that slides and or pivots.
Step five: Run it like a game winning touchdown and show everyone around you that too much lube is a mug fat myth .
Lubriplate with a Q Tip any shiny spot/streak, wipe off excess with dry towel. Done. USMC method, 1975. My A1 never failed me.
I always soak the gun down with oil when in use.
RSO from Colorado here. It's amazing how many people come to the range with absolutely dry guns. Being high altitude I notice that when people leave their dust covers open, the oil tends dry out a little bit faster (true for multiple brands). The process described in the video is exactly what I do to my guns and it works perfectly. I recommend this to my clients as well. I like how you present the information and focus on the why. Thanks.
Funny I went to the Colt armorers class a few years ago, and they taught us to put one or two drops in the two holes on the bolt carrier that the gas rings pass by. Thus lubricating the gas rings so they would not wear out. Hmm I wonder who is right?
Thank you for your service!
For a rifle that is going to be loaded for substantial periods of time, such as a law enforcement duty rifle, lubricating the bottom of the bolt carrier will bring oil into contact with the top rounds of ammunition in your magazine. This may cause malfunctions on a life-saving tool if said oil penetrates the casing or primer.
That one point is very poorly advised for duty use.
Nobody lube the rings? The actual piston rings since we’re all relating to car engines here lol
All I personally do to the exterior of the bolt carrier is put a few drops of lube on it, spread it evenly, rub it in and wipe the rest off. Then I lube the cam pin lightly and the bolt itself only on the part that slides in the bcg, maybe a drop total. You don't want oil all the way out front that'll wind up in your chamber when it goes into battery. That's supposed to run dry. Never understood guys running soaking wet BCG's.
Nice information! Thank you for your service!!