Following up on my recent purchase of a S&W M&P 15 Sport, what is the maintenance interval and type(s) of cleaning methods to clean the gas impingement tube?
How do I tell when it needs cleaning - besides when the bolt won't cycle?
Does cleaning require removal of the front A2 sight? If so, does this mess up the zero? Maybe a lame question, but I haven't had that part off the gun yet.
I learned when I was 6 that I can only disassemble an alarm clock so many times (once) before it won't work any more. Trying not to do that to my firearms....