SmythBusters: Galvanic Reaction & Your AR-15 - Part 1
Our intrepid Brownells Gun Tech™ duo Steve Ostrem and Caleb Savant tackle another Internet firearm forum myth: galvanic corrosion on AR-15s. A galvanic reaction is an electrochemical process that occurs between two dissimilar metals in direct contact with each other - such as the aluminum of an AR-15's receiver and the steel of its barrel - that results in corrosion. The guys did intensive research, they talked to top AR-15 manufacturers including Sons of Liberty Gun Works and Geissele Automatics (watch Bill Geissele's response linked below), and the answer is... There's NO such problem.
Here's the deal: ALL AR-15 receivers are anodized, and barrels are usually Parkerized, blued, or Nitrided. These finishes are non-conductive. They prevent the two metals from being in direct physical contact with each other, so the reaction can't happen. Some folks think AR-15 barrel threads have to be lubricated to serve as insulation to prevent galvanic corrosion. Nope, says Caleb, you lubricate the threads to make it easier to torque the barrel into the receiver. The bottom line: you'd have to do something really funky to your AR-15 to cause a galvanic reaction. If you HAVE personally seen galvanic corrosion on an AR-15, tell us in the comments below. Even better, send us a photo!
