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What does it matter ?

I thought the interesting posts in that thread were made by "BigRx" who professed technical knowledge in the science of lubricants. He pointed to various criteria demonstrated by tests such as the "Timken OK load" test. For me the objectivity of scientific testing carries more credibility than tradition.

I think any good EP automotive grease is suitable when used properly.

Glad you liked the link.

Curl

Ah, but there is a relationship, my stupid (again your words, not mine) friend-lubricants sold with the PTFE label attached COST more, regardless of use described on the label, and, honestly, people who buy them thinking they are getting something for their (extra) dollars, or rupels in Genos case (good to see that huxterism is truly a universal phenomenon-can you imagine the guffaws the marketing people suffered when they told us, in their advertising, that PTFE was the "most slippery substance known to man" and then, a sentence or two later, that this same slippery substance would "instantly bond to any metal" knowing folks like you would lap it up like chocolate sauce on a free ice cream cone?) spent seem to have missed the Dupont chairman's brutally honest answer that PTFE is not a lubricant.
It is hard to get around that FACT.
You pay more, and get less. And, you advise on a public forum, to do the same, idiotic thing you do. Oblivious to the fact that, regardless of application of oil with PTFE in it, nothing, and I mean nothing, has been gained. Not on a gun, not in a crankcase, not in two stroke oil, not, in fact, anywhere, in any petroleum product, it has been tried.
Oh, by the way-much as I would have liked to, I've never actually owned a model 31. Mix that in your cocktail, along with those anti-dementia medications that an able bodied, and (hopefully) younger, person administers to you. No doubt, an old timer like yourself can explain to all of us the truth of the statement, "Memory is the second thing to go".


Best,
Ted

When you're collecting Whale Sperm Oil, isn't it best to find a friendly whale or do they automatically become friendly, as soon as the collecting starts? On a more serious, if less romantic note, neither oil nor grease "collect" dirt. Dirt will stick to either. Grease(my preference) will stay in place longer. the light oil used in old style air cleaners is there to give the dirt particles something to stick to, as they are brought through the filter by the air being sucked into the carburetor. They are not "attracted" by the oil. The important things, as many others have said, is to frequently clean off the old and replace with new, whether it's oil or grease. IMO, hinge pins or trunions ARE high stress areas because of the load placed on them(opening and closing the gun, cocking hammers and operating ejectors or extractors), not because of high RPMs or high heat.

I would think the forces generated by firing the gun produce high stress also. It is said that grease is important for its cushion effect.

Again, I'm no expert, but I think a good modern grease is perfect. Use sparingly. Keep it clean and renewed.

Curl

A few thoughts on lubricants for firearms.
First, hinge pin lubrication requires a high pressure lubricant for best performance. These lubricants are typically high viscosity fluids such as bearing greases with special additives to prevent metal to metal contact - in a bearing during rotation or in a double during firing. Oils will not provide effective protection during firing over a long period of time. If you look at the specs for Mobil One bearing grease, it indicates that it has additives to “impart extreme pressure properties” which is what you are looking for in a bearing or hinge pin grease.
PTFE is a solid as stated earlier in this thread and is actually a micro sphere of PTFE (Teflon) suspended in a carrier. In an aerosol can, it is typically a volatile carrier, in liquids it is the “oil” component. These work by providing a large number of these micro spheres to the pressure surfaces where they are deposited as a film of sorts. This only happens with pressure so if you spray the material on and wipe it off, it is likely you have taken most of the PTFE off in your cloth. It does not bond to the surface without extremely high temperatures or some pressure to cause the polymer to conform to the metal surface.
Precision surfaces with relatively low to no impact force, such as sears, ejectors, etc can be lubricated with a light oil to provide appropriate separation of the metal surfaces. Grease will also work but not as effectively as a lower viscosity oil for this application.
In all of these gun lubrication scenarios, if you leave the grease/oil on the gun to accumulate grit, you have made a wonderful polishing compound. Over time, this will slowly erode the precision fitted surfaces and make them out of tolerance. The way to resolve this is to clean the surfaces each time you use the gun and replace the layer with a clean layer. Certainly modern lubricants can absorb some level of contamination and still function but, at least for my guns, a cheap “clean and replace” of the lubricant is the best approach.
For those curious, I use STOS for all high pressure bearing surfaces and Break Free for all sliding surfaces with low pressure and I replace the lubricant each time I use the gun.
Thanks
Z

On a properly fitted pin and hook there is no movement on firing so there is no need for cushioning. The same goes for supposed stress of cocking, operating ejectors/extractors and what stress is involved with opening and closing the action? The hook and pin are a simple hinge with little bearing weight. I maintain that there are many many double guns that are quite functional, tight and on face after many years without ever having the pin and hook lubricated with anything more sophisticated than an occasional wipe down with sewing machine oil. Keep the pin and hook clean and free of corrosion, which only requires a slight amount of corrosion resistant lubricant, shoot ammunition that is appropriate for the gun and the gun will out last you. I have a 125 year old LC Smith that is tight as it was when it left the finishers bench in Syracuse in 1887 and a whole bunch of guns that are about half its age and absolutely non are loose at the hinge. Now over that time period I would suspect all never saw the likes of RIG, certainly not turbine engine oil and until recently anything more high tech than Breakfree applied to the hook and pin during routine cleaning. This has been a fun exercise but in the whole quite useless.

Actually, if one examines what is typically found in polishing/lapping compounds, you will discover pretty quickly that the grease/carrier is almost always water soluble, meaning it is water based, and has no load or shear strength, and the abrasives are pretty intense, typically, silicon carbide, garnet, boron carbide, aluminum oxide or diamond. The grit that accumulates after firing a gun, lubricated with a good quality, EP grease can't begin to compare with these, and good quality EP grease will hold a quantity of debris in suspension, where it can't hurt anything, by design.
I think it was McIntosh who originally compared the two, and it is a bit misleading. The debris that results from firing a gun, if mixed with a good quality EP grease, will be a very inefficient lapping compound.
That doesn't mean you shouldn't keep it clean, but, you have more time and far better lubrication than if you did use valve lapping compound.

Best,
Ted

If there is no movement between the hinge pin and the corresponding "hook" the gun could not open. There is some and that small amount of movement will be magnified over time. Try to take a new wheel bearing and find lateral movement in it and there is essentially none (typically a few thousands) but it is enough to allow rotation - but also enough to have an issue with impact pressure, which is what bearing greases are designed to do. Calculate the pressure of firing on the relatively small effective contact area on the hinge pin and you will find extremely high pressure effects, although for very short times.
Can virtually any lubricant work - yes but not optimally. That is why there are a variety of lubricants that are available. You can choose to use them (or not) and prolong the life of your firearm as you choose.
Thanks
Z

Great attempt, but, I think you are wasting your time with him-if he didn't understand that zero clearance=zero movement, when he typed that less-than-well thought out response, and some clearance=need for lubrication, you might as well be at the beach.

Best,
Ted