AR lubrication.

[OilyPablo]

As noted some undergassed rifles do get bogged in the sludge. But I say this doesn't apply at all to rifle cartridge ARs. Run the rings wet with a lube that doesn't coke too much and you just won't have problems other than a little bolt scraping every 3000 rounds or so.

 

[Tomac]

I use Mobil 1 0w40 "European Formula" on all my AR's, it's one of the few Class IV true synthetics.
Tomac

 

[Sapper771]

While we are on the subject, what weight of Mobil 1 do you prefer and why? I normally use 10W30, but wondering if the other weights (0W20, 10W40, etc) would have an advantage? Thanks in advance.

 

[d2wing]

0W20 is what I would suggest. I would not use regular motor oil, I would use only a synthetic because regular oil can build up sludge and be very sticky in the cold.

 

[Arizona_Mike]

A typical (over gassed) 5.56 or 6.8 AR won't be picky at all about lubricants. Use something like this guide:





If somehow anyone has an undergassed beast like a pistol caliber or .300BLK subsonic, then I highly advise polishing all those key moving parts on the BCG and then using Militec or the like.

What are L and G? Light and Generous?

Mike

 

[OilyPablo]

Yes sir. Somewhere is another drawing with the Light and Generous in hand signals.

 

[rbernie]

What are L and G? Light and Generous?

Yes, that's my understanding.

 

[Tirod]

Look again at the bolt, rings, bolt tail, and carrier.

First, when gas residue is directed into the gas cylinder, the rings seal the front of the chamber, and the close fit of the bolt tail seals the rear. As the bolt cams open, the gas rings pass the gas ports on the side of the carrier and gas is ejected from the cylinder. Often you can see it, especially in the first few shots when excess oil is ejected along with the pressure. The Coke bottle effect is happening - high pressure inside the container carries the contents with it out the opening.

Put 300 rounds thru it and no, there isn't a sludgy mess. It was ported out early on. Those of use shooting blanks with muzzle adapters have seen more of it, but that is deliberately trapping some very low grade powder in the action. Suppressed shooters see that, too, after shooting large amounts of ammo.

As for scraping the bolt tail, it's a hot topic lately, and would seem to be required by the service. In reality, no. What Command and armorers are doing is directing that soldiers keep busy, justifying the training schedule, and not roaming around on post getting into trouble. We are talking about 18-24 year olds with no GF close at hand to keep their attention away from other risky activities. Armorers don't want to do the dirty work, either. They tend to have a life and like to get out of the Company at the end of the work day.

There is also the fit of the bolt tail in the carrier. There's no room for another set of rings, so the close fit is all that can be done. It's a calculated leak - and having some gas residue on it helps seal it better. Extensively scraping the bolt tail opens it up, letting more gas thru, and changes the milspec dimension, altering the amount of pressure in the cylinder.

The story of Filthy 14 comes in at this point, a loaner carbine that has gone 60,000 rounds with only two cleanings. It just gets lubed and wiped down. It's had patches down the bore twice, and nobody reports they've been scraping the bolt tail. In fact, that tool didn't exist until a few years ago - the first 40 years we just used the chamber brush to get most of the residue off. That is all that was needed to satisfy the armorer. We had other check points of a more administrative nature they liked to pull on us, like carbon in the tiny holes where the gas tube enters the upper.

You can make too much about cleaning the AR15, and those that sell tools to do it aren't in the business of saying they aren't really necessary. The whole "AR's poop where they eat" mentality has been selling a lot of stuff for a long time and all too many have bought into it.

Just lube and wipe off, leave the cam pin channel runny, and shoot it. The Garand is more prone to gas residue build up requiring gunsmith level disassembly.

 

[briansmithwins]

The story of Filthy 14 comes in at this point, a loaner carbine that has gone 60,000 rounds with only two cleanings. It just gets lubed and wiped down. It's had patches down the bore twice, and nobody reports they've been scraping the bolt tail. In fact, that tool didn't exist until a few years ago - the first 40 years we just used the chamber brush to get most of the residue off. That is all that was needed to satisfy the armorer. We had other check points of a more administrative nature they liked to pull on us, like carbon in the tiny holes where the gas tube enters the upper.

From the SWAT magazine site: https://www.slip2000.com/blog/s-w-a-t-magazine-filthy-14/

Brady, Texas, in March 2009, it suffered a malfunction, which was reduced with Immediate Action. The bolt was wiped down at 6,450 rounds.

At Prairie du Chien, Wisconsin, in May 2009, it had several failures to extract, and the extractor spring was replaced at 13,010 rounds. This is far beyond the normal extractor spring life under these conditions.

At Wamego, Kansas, in June 2009, two bolt lugs broke at 16,400 rounds. We replaced the BCG. Considering the firing schedule, this is within normal parameters.

At Columbus, Ohio, in November 2009, we had several failures to extract at 24,450 rounds. The shooter gave it a field cleaning and replaced the extractor and extractor spring.

The rifle has had several components replaced during its life of filthy squalor.

BSW

 

[benEzra]

I have heard of using motor oil. It would seem to me that Mobile 1 might be an excellent choice, it still lubricates at 800 degrees. Normal motor oil starts to break down at half that.

I have used Mobil 1 for years on AR and AK internals, and IMO it is one of the best gun lubricants on the market, with much better lubrication properties than a lot of mass market gun oils. I personally use 5W30 EP because that's what I put in my car, and it is typically made from better base stocks than 10W30 anyway due to the wider viscosity range. I've heard of people using everything from 0W20 to 20W50 or whatever, but just be careful not to go too thick in cold weather. 5W30 should be good down to well below zero.

Unlike petroleum based oils, M1 doesn't dry out or turn to gum, and it firms a thick film that lasts a long time. Just don't oil the outside of the gun with M1; thick, long-lasting oil films are great on the internals but are lousy for handling. I use Rem Oil (thin, fast evaporating) for protecting external surfaces from rust and such.