RIG products are no longer available. I can recommend these products personally http://www.wallysoriginal.com/genpurposegrease.php. Wally has been at gun shows all over the east coast for many many years. I have used this grease to protect all kinds of metal from rust forming from this humid east coast weather. Additionally it smells a lot better than RIG. It just has that "right" gun smell, if you know what I mean. I am sure you do.
I must agree with SuperXOne, Petroleum Jelly has been used for a good many years by my family for most of our firearms, etc. With few exceptions it makes a great rust preventative. Snobs not-withstanding.
Anecdotal, but here goes anyway. I worked for Mosler Safe Company for 8 years back in the 80's. Part of my responsibilities was to service combination locks on safes and vault doors. The only lubricants we were allowed to use were Vaseline or Lubriplate 130-A. The reason we were given is that these will not harden or dry out. I have used the Lubriplate 130-A for many years in many different applications. It is a Mil Spec product and Brownells has it. Since Lubriplate is a Lithium product and is white, you probably would not want to use it as a rust preventive.
I have also recently (for about 2 years) been using TW-25B grease. As a lubricant it is excellent.
Well, if they've brought back the Rig Universal and the Rig Rag, that's certainly good news. Hope they bring back the Rig +P. It was the slide-rail lube of preference for a rather elite group of 1911-style pistols I once knew ... rangemasters, TAC unit guys, etc. Serious master blasters. Most of 'em shot Wilson Combat modified 1911s. I used the Rig +P on my stainless Gold Cup Commander (a limited run gun) and found it performed quite nicely.
Basically any grease is fine as long as you clean it off and replace after every day of shooting.
I've used in the past:
Mobil 1 Synthetic grease (I think Shooter's Choice grease in the syringe is repackaged Mobil 1)
Tri-Flow Grease and Super Lube Grease which I think are the same
Krieghoff Gun Glide
and others I can't remember
I still have good supplies of all of the above and use all of them except the Hoppe's because the last tube I bought had something wrong with it and it seemed like the lube had separated from the soap. Whichever is most handy to where I am when I'm putting the gun together is the one that gets used. I think from a technical perspective, the Perazzi Grease is the best but it is a pain to clean off and the others seem to do just fine. The Mobil 1 is by far the cheapest because it can be bought by the pound in any auto parts store.
I think I would recommend staying away from petroleum jelly. Best I can recall is that it melts somewhere around 150 degrees F which means its lubricating properties will be lost long before that. It does make a good rust-preventative but don't let it soak into wood.
If you haven't tried Slide Glide yet, you may want to give it a shot. It's one of the best greases I've ever used. Also, according to a test I read a while back (I can't recall where, unfortunately), it exhibited some great corrosion protection properties as well. I use it on the action bars of my shotguns (when the weather is not frigidly cold), and I also use it on some of my tighter fitting handguns (1911's, Sigs, etc.) and it does a great job. You can also get it in different weights, depending on the application.
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