silicone oil
 

I was able to make a propane adapter for under $10.00, now for the silicone oil! I have read in MANY places that you can buy the oil at Walmart, Canadian Tire, Michaels, ETC. but they don't seem to know what I'm talking about, everyone I have talked to asked what it is used for? and I can answer them cause I don't know. So does anyone here know what it would be used for? things like sewing machines, air tools, ETC any ideas.

Hobby shops usually carry it. Make sure you get 100% silicone oil, there are a lot of half and halfs floating around that aren't good for your gun.

It's sold under the name "RC Shock Oil" at RC Hobby stores (make sure to ask if it's 100% silicone oil).

You'll want something like 10 or 15 wt. oil (or 5 wt. if they carry it but in my experience not that many places do). The AI silicone oil is supposed to be 1.5 wt. but you can't get that as a regular consumer, that stuff is for commercial applications or so I've been told (you basically have to buy an entire "barrel" of that stuff at minimum is what people tell me (~160 Litres)) so you have to buy it from AI themselves (since they package it into smaller packages that are useful for consumers instead of a big barrel worth of oil that will never be fully used unless it's for an entire field that only runs GBBR's).

Aside from airsoft guns and RC what else is the oil used for.

In North America? Very little that you'd have access to. It would have to be sourced in large barrels as well. It's uses are mainly industrial, such as in medical labs, in the food industry, distilleries, and pharmaceutical manufacturers. "Airguns" is listed as one of the large industrial uses of it as well as paintball.

It's because of the inert, non-toxic, and protective qualities of silicone that allow it to be used in these industries.

Your best bet if you can't find an RC shop, is to check out local paintball shops and fields. They would use very similar (if not the exact same) oils.