Stickman,
As per the instructions on the Do it your self section here, I cleaned the FCG with CLP prior to installing. This morning I took the FCG out again, cleaned again, checked the FCG for any metal shaving, dirt and debris. I cannot see a way to check if the disco spring went in the right way, as there doesn't seem to be away to remove it, as someone stated, the pin is flattened (this is how it came from ADCO, the FCG is a RRA 2-stage trigger tuned by WOA).
theshootersden,
you are correct, my rifle had the original, standard FCG and I then switched to a 2-Stage FCG once the problem started happening. This again started happening once I switched to FAE .223 with brass stamped with the NATO symbol and LC04. Like previously mentioned, I was using PMP .223, and ran through about 5k rounds with no problems. I'm going to use some XM193 and Q3131(a) my next time out to the range, just to see if its the new ammo thats giving me the problems.
Thank you to everyone for their help.