Spent case ejection path is all over the map,

Is this the same ammo throughout the mag??????

You have some ejections in the 5:00 positions that are correct, then as the ejections start to move to 1:00, you can see the jam coming a mile away.

So be truthfully, don't see the problem with the rifle, but rather how you are cleaning and lubing it instead.

Switch over to BreakfreeCLP (16oz spray can) to clean everything on the rifle, including the chamber with a chamber brush by hand, but not  the bore.

Start off by pulling the B/C (pull it down for cleaning), buffer and recoil spring, and give them just a light coat of CLP right on top of the fouling.   Now on the upper, start by cleaning just the barrel bore with Sweets.  Sweets is aggressive as hell, so it won't take a lot of scrubbing to get the copper out, and clean the bore until you are pushing dry patches out (that are no longer blue).  


Now give the chamber a good shot of CLP, break out the chamber brush, and go about scrubbing the chamber.  Now give the chamber a fresh shot of CLP (including a quick shot of CLP down the tube from inside the receiver), then start pushing dry patches down to bore until they come out clean.   As for why you are cleaning this way, Sweets will not leave behind any short storage lube on the bore, but the CLP will even after you think that you have it bone dry, and why you use Sweets first on the bore, then CLP for the chamber afterwards.

Now on the lower parts, since the CLP has sat on the parts for a few mins (has a cleaner in it), most of the fouling on  those parts should just wipe away (will have to do a bit of scrubbing on the back of the bolt gas section through0.

Now to lube the rifle, you going to love this!!!  Spray a coat of CLP on both the inside and outside of the assembled B/C, give it a single flick to knock off a tad of the CLP, then install the B/C wet, followed by a few dry charges to migrate the CLP to the upper bearing areas.

Now since you just have to rampage with the rifle, about the every 200 round mark, pull the charging handle back just enough so you can get the gas rings forward of the gas ports on the carrier, and give a quick shot of CLP into the gas ports (Few drops if you want to shoot the CLP into a small bottle to use it that way instead).   This will put new CLP in the gas section of he B/C, which will remigrate the new CLP back to the upper bearing areas (not only to relube the parts, but since CLP has a good fouling cleaner in it, so it can clean the parts as you are shooting as well.  

So to bottom line it, never think of it as cleaning the rifle, but rather just changing the lube in most of the rifle instead.  With the rifle cleaned and lubed this way, should be able to burn through a case of ammo or more in a sitting, and the rifle still running just fine.