DAR 701, I take it you own a nice Canadian made AR? I can see oil being a problem in a tighter fitting rifle like that and agree with running anything like that dry. The SKS is a whole nother animal though. It is loose fitting so it will stay reliable after being drug through the mud, covered in dirt, dropped in a river and lit on fire. You would need a massive amount of crap in there to stop an SKS from cycling with its oversized gas port and loose fitting gas piston. I have found that lighter oils work well on the gas piston, Ballistol Klever and M-pro7 work well and clean very easily after shooting. I have a feeling Birchwood Casey Barricade would be even better as it is very thin. Cheaper, heavier oils that will dry out easily would gum up quicker and be harder to clean, the 2 I listed are not and clean easily. I like to run a dry patch down the barrel before shooting as it comes out much cleaner after shooting than being oiled, and when I remember I wipe the gas piston too. Oiling everything after cleaning lets you get away with not having to do any voodoo witch tricks like windex and boiling water to prevent rust. Boiling water or windex has never touched my red rifles, and they never rust when oiled.