King Arms M4 - Selector switch problem

[XZIVR]

Can't see how that would affect the selector. Most likely you did something different when putting it back together that happened to fix it. I've had problems with the selector on my receiver and found the biggest effect on the selector stiffness is the order in which you tighten things and how tight you make them. For instance the grip, if tightened before the stock, would cause the selector to be tight on mine. Tightening the screw on the stock first would consistently and repeatedly solve the problem.

[justynmagz]

Well I must have put it together the right way by chance because I swear I took it apart and tried 10 different ways. Good call with tightening the stock first...I will keep that in mind next time I take it apart.