I've used synthetic transmission fluid for years. Works well and is as inexpensive as anything you can find.^^^this.
I think gun lube is over rated. Read an article years ago scientifically dissecting the subject and it suggested the best gun lube was ATF (sorry lost old bookmark...). For a while I also used Marvel Mystery oil just fine. Then more recently I picked up some CLP and FP10 because I bought a new gun and the mfg recommended it only for their proprietary finish coating.... so Im working my way thru those but will probably go back to motor oils. I dont see how any gun will get as much use as the inside of an engine block or trannny yet the application is the same.
edit, I opened some google-fu and think this is the old bookmark I had. He liked ATF but recommended Lubriplate’s FMO-AW oil
Introduction Firearms enthusiasts are the targets (pardon the pun) of some of the most misleading advertisements regarding the proper lubrication of theirwww.grantcunningham.com