Hi. Thankyou everyone who responded to my posts and helped me with my first AR build. Today it finally got assembled; PSA pencil profile midlength, S&W lower, PSA LBK, Spikes f/a carrier courtesy of a friend, BCM medium charging handle, and a Magpul handguard to replace the cylindrical one that came on the upper. I am short a rear sight, and not wanting to be too spendy here. I will most likely mount a nice airgun scope which I already have, 3-9x40, but would like a rear sight as well. The front sight is standard. Any advice? Thanx again folks, tk