Gun Lubrication

There are a million wonder oils and greases for guns out on the market, and most of them are no better than some very simple, inexpensive, and common lubricants you can buy. Some are actually harmful. The best source of information I've found on lubricating guns comes from legendary gunsmith Grant Cunningham's "Lubrication 101" essay.  I recommend you read it, but I'll summarize it briefly:

You need two products: An oil, for small parts that carry a heavy load, like triggers, hammer bushings, and pivots of all sorts, and a grease, for parts that slide or rub together, like slides, bolts and sears. The oil should be thin enough to migrate into bushings and around pin, and the grease should be thick enough so that it stays where you put it- and no thicker. There are further requirements, having to do with corrosion resistance and so forth, and if you're interested, read Grant's piece. He explains all the details, as well as why you should never use any chlorinated compounds anywhere on your guns.

Back in the 18th Century and well into the 20th, the preferred oil for small parts under high loads, like clock movements, was whale oil- specifically, sperm whale oil. It has great lubricity, handles very high loads, and never gums up. It was also a major component of Dexron, the first automatic transmission fluid for cars! Whales are no longer hunted for their oil, but there's an excellent substitute- yep, automatic transmission fluid. Any Dextron-type fluid makes a great gun oil, and you can get it for as little as $4/quart- which is a lot cheaper than the $15 or so you'd pay for a 4 ounce bottle of someone's magic gun oil.

A good grease is cheap, too. Grant likes Lubriplate SFL in its lightest weight- NLGI #0.  For hot weather, a slightly heavier (but still very light) SFL is called for. Lubriplate's Lubriplate 10oz Low Temp Garage Door Grease, which is a NLGI #1 SFL, is a good choice and probably available at your local hardware store. That 10oz. tube will probably last you several years.

About that photo at the top of this post: If you haven't gotten it by now, it's a US WWII-era M3 "Grease Gun." Get it? Never mind.