For all the advances in polymers and Hollywood nonsense about plastic guns, metal remains the fundamental building block of firearms. And where there is metal, there are many options for how to treat, finish or coat it. Long past the days of just choosing between bluing or raw stainless steel, we now have a veritable bounty of options. Each has a certain set of characteristics that may make one or another more suitable for your particular needs. Read on to learn more.
KEY CHARACTERISTICS TO KEEP IN MIND INCLUDE THE FOLLOWING:
Hardness, durability and wear resistance: For hard-use weapons, whether for duty or competition, this is often a key consideration. Thousands of presentations from a Kydex holster, thousands of rounds through a barrel—this will take a toll on metal. For our purposes, standardized hardness testing is measured on the Rockwell C scale (HRC) and Vickers (HV) scale, by putting an indenter under load against the surface.
Corrosion resistance: Carry guns pressed up against your sweaty body or used in maritime or humid environments are often a recipe for rust and corrosion. It’s not a license to abuse your gear, but finishes intended for this purpose can help a lot—of course, remember that nothing is truly corrosion proof. While it cannot exactly represent real-world performance, a standardized salt spray test (ASTM B-117) is typically used to assess the corrosion resistance of materials and finishes. In such a test, the parts are placed in a testing chamber and exposed to a dense fog of 5 percent salt solution until they begin to show the effects of corrosion.
Lubricity: Many finishes have very low coefficients of friction—a measure of how easily one surface slides against another. For example, the coefficient of friction for steel on steel is over 0.7 dry and around 0.2 with lubrication, which is more than halved by many of the coatings. Again, we always advocate properly lubricating your weapons, but these finishes enhance performance and provide you with more leeway in your maintenance schedule.
Type of material/substrate: Some finishes or treatments can only be applied to steel, not to aluminum or polymers.
