Brian Enos' Slide Glide lubricant is my preferred lube.  Works especially well on Glock pistols.  You know that gritty feel and sound you get when you cycle the action on a Glock? Use Slide Glide and it's gone. I use SG #1 on my stock guns and the SG Lite on my open gun. I use it on the slide rails, trigger bar/connector contact points, barrel, barrel lug, guide rod, and recoil spring areas. Engineered to have a stringy characteristic that allows it to continually drag itself back into the friction areas of the gun. You'll see immediate results while hand cycling or actually firing the gun. Also works great on your reloader ram and rails. Available in two weights or viscosities.  Slide Glide #1 is the standard weight, and is engineered for stock weapons in temperatures over 45 degrees, or open guns with "loose" top ends.  Slide Glide Lite is engineered for open guns in all temperatures, or stock weapons in temperatures lower than 45 degrees.  Slide Glide #3 is the heavy viscosity lube that works well in Glocks, stock guns, or loose open guns in temperatures above 80 degrees.