This is a good thread about galling, and I am glad you brought up the subject.
I am an advocate of the synthetic lubricants like the grease that Neil has for sale. Just a small amount of this will stop any galling effects and you will protect the metal to metal contact. Firearms are like an auto engine; the bearings on the crankshaft are metal, the oil in the engine keeps the rods and crankshaft for making any contact. When you lose oil pressure, there is metal to metal contact and you know what happens then.
A pistol slide and moving parts are sort of the same way; keep metal to metal contact to a minumum. With some parts, oil works great, where you have sliding contact, a light coating of grease is advisable. When yo have contact where the parts create a lot of pressure, you need a high pressure lubricant so it will not be "squeezed" out from the two surfaces.
A very economical lubricant is the high pressure wheel bearing lubrican used in your automobile. It works great and is cheap!
I like to shoot my M1A rifle and I like the sythetic lubricants on the bolt and operating surfaces and it has worked for me since the 1970s.
Marvin
AMMOMAN