Re: Suggestions on a BCG malfunction?
This is not an unusual problem.
Literally, just finished helping out a friends AR tonight.
#1 - LUBE the buffer tube, spring, and buffer. Lube the tube, outside of spring, outside rear of buffer (slides on the inside of the spring), and the large rounds of the buffer. I HIGHLY recommend STOS from Ponsness Warren - 100% synthetic, does NOT sling, and lasts a long time. A little dab will do you.
#2 - Polish the chamber! Flitz or other NON gritty metal polish on a shotgun bore mop with a low speed drill is nothing short of wonderful. DOWSW with carb cleaner (pull the gas block first).
#3 - lube the BCG. Again, a dab here and there...and manually cycle the bolt when it is out.
#4 - ammo - if you are reloading, 16" barrels, generally operate better at max loads.