Quoted:


Sorry, I just can't get emotional about gun lube.  

{Joke.  Just joshin'. }

Quoted:


OK.



Here's a little test I did a while back. Pieces of steel were ground and placed on a board, then a paper towel saturated in the oil was wiped over the steel, then a saturate solution water and table salt was sprayed on the board/steel. Here's the result. Triflow, G96, WD40 and Hoppe's #9 were the best. The motor oil was next. Two guncleaner/fouling solvents I made up were after that. Kerosene was about as bad as bare steel {control}.



http://i38.photobucket.com/albums/e115/Skaapskieter/Corrosion%20Test/RangeDaySHTFChallenge04302015%20008%201024x768_zpsi2li61zl.jpg



http://i38.photobucket.com/albums/e115/Skaapskieter/Corrosion%20Test/RangeDaySHTFChallenge04302015%20011%201024x768_zps9523bc1v.jpg

Quoted:
Pro:  it's cheap.

Cons:

1.  Not really a very good gun lube.
2.  Poor resistance to oxidation.
3.  Poor corrosion protection.
4.  Generally toxic.

But, it is cheap and a lot of people use it.

Quoted:
I know of no downside to use of synthetic motor oils for lubrication of AR15 rifles and plenty of positives.

1.  Direct inpingement gas systems run very dirty and have much higher levels of carbon than piston type semi-auto systems or encountered in bolt guns.

2.  The type of carbon and the manner in which it is deposited is very similar to what happens inside direct injection engines, especially those with turbochargers.

3.  The operating environment of turbocharged direct injection engines, both gasoline and diesel, is very hostile, involving temperatures that approach 1500 degrees at the oil passageway surrounding the bearings in the turbo.  The center shaft being protected by that oil spins at over 100,000 rpm.

4.  Those engines run extremely low air to fuel ratios.  That means the combustion process is super rich.  The oil is much more prone to fuel dilution, and the residue that is left behind is very thick, dark and baked on carbon, if it is not picked up in the oil.

5.  There are detergent additives in this type of motor oil that are especially designed to keep carbon deposits from sticking, or make it harder for them to do so.

6.  The oil has to last a long time under these operating conditions, at least 3,500 to 5,000 miles.  The number of combustion and exhaust cycles in such an engine in one minute of operation is probably more than an AR15 will endure in its entire useful life.

7. The viscosity of the oils, typically 5w-30 or 5w40, is ideal to cling to the parts in our rifles without running off or becoming sticky.

8.  These oils seem to prevent or greatly reduce the tendency of nickel-boron BCGs  to stain, if you elect to run one.

9..  Even the highest grade synthetics, like Mobile 1 or my favorite (a turbodiesel variation), Shell Rotella T-6, are only about $6 per quart.  While that may be expensive for motor oil, it is very cheap compared to the various snake oils offered for our rifles, that may cost that much or more per ounce.


For these reasons, I think that these synthetic motor oils (not dino oil), especially the diesel formulations, are extremely effective at protecting our rifles.

I come from an automotive engine remanufacturing and machine shop background.  I am dumbfounded at the suggestion above that synthetic motor oils so formulated are prone to oxydation or do not provide corrosion protection on steel or aluminum materials used in our rifles.  We don't see these issues in engines, not on the cylinder walls, not on the pistions or other lubricated parts, not on bearing surfaces.  And I don't see it rifles.  Nor do I find any support for the notion that synthetic oils, including the additives, are toxic or hazardous.  I have the MSDS for T-6, and can discuss it at length, if anyone wants to read it and ask questions.  Google and download it.  Read it first to save us some time.  I'l give you one hint:  The toxicity is low even for human ingestion.  I'm not suggesting that anyone swallow it, but it won't hurt you if you do.

I do use Breakfree CLP or some clean up purposes (not lube), but frankly, prefer simple mineral spirits for that.

There are a lot of companies making a killing on selling gun specific snake oil at outrageous prices and profit.  None of these are better than high grade synthetic motor oil for lubrication purposes in an AR rifle, and most are decidedly worse.  Any that perform at close to the same level are probably almost entirely synthetic oil similar composition and viscosity as Mobil 1 or Rotella T-6.

I refuse to buy into the hype of those high priced gun oils.