OK, so range report update (and I'm sure someone will have pics to me soon, ahem, Misanthropist).
I received the nice and clean rifle from WP late last week, and only got the one day to test it out before the course. It ran great. However, once on the course I experienced a total of 18 failures to feed, and one failure to extract. All ammo was Winchester white box 55gr. Initial thoughts were that the training mags (Pmags) I was borrowing from an agency attendee may have had weak springs after years of hard use in their department. However all those mags functioned flawlessly in his rifle. Using new GI mags and new Pmags plus lubing the bolt/carrier group seemed to fix things up Wednesday night for the night shoot.
A wipe down when I got home and relube plus a good nights rest seemed to bring the demons back. Finally after shaking my head, having Hackathorn look at it, two AR5 armorers look at it, I yanked the buffer and spring, dry as a bone with carbon flakes all over. wiped clean, lubed, and the rifle ran ####ing perfect from there out. I will admit, I'm not an AR SME, but that seems to have been the issue all along. Obviously I should have looked at that spot near the start of the diagnose stage. But the mags seemed to be the culprit day one, and as I mentioned, outside my normal scope of expertise. That's changing.
So end result? WP, your gun runs perfect now, and One Shot, no worries, I still want one I like it that much. I will however make sure the ####ing spring is lubed when I get!
KevinB, or anyone else, how much of an idiot am I for not looking at the buffer spring right off the bat? Cuz I don't think my Colt has ever been lubed outside of the original factory assembly?