Out the gate, have you correctly cleaned the rig, hence something like sweets for just the bore, the chamber with a chamber brush and CLP, and the rest of the rifle with CLP as well?   When you where done, did you remove all the fouled CLP (loaded with assembly/storage grease), the lightly lubed the upper receiver bearing areas with fresh CLP?  When rifles are built, grease is used, and it has to be removed (and the debries that it collects) before the rig is put in service.  Hence CLP has a good cleaning agent in it, so not only is it about the best lube for the rifle, but cleaning agent short of the copper in the bore.
Note, do not use Hoppes solvent to clean the AR, since it and CLP will create a sticky mess.  Don't use Hoppes gun oil as your lube, since it does not have a cleaning agent in it.

Next,
If when you pull the charging handle all the way back,
the last inch'is of pull is the same tension as the middle of the pull,
The face of the bolt stops 1/8" to 1/4" in front of the back edge of ejection port,
And the empty mag follower is raising up the bolt catch to catch the bolt via the front of the bolt face (read bolt catch is moving freely in the lower bolt catch slot as well).

Then next comes to firing only a single loaded round in a mag for effect (with the empty mag lefts in the mag well..  The correct effect should be that the spent case is ejected 10' to 15 to the 5:00 position (forward if it hits the upper receiver defector on the way out), and the bolt locked back by the catch via the catch in front of the bolt face.

If no on the correct distance and patch of the spent case, then go find the spent case a take a very good look at it.  If the sides of the case are fouled or scratched to hell via the freshly cleaned and lubed rifle, then you have a problem with the chamber either still not cleaned correctly, or reamer chattered to hell instead.

If the spent case rim is bent to hell by the extractor with the sides of the spent case still shinny/no marred, then the action is getting too much gas.  If the clean spent case does not have a bent rim, then the rifle is under gassed or binding instead.

For binding checks, pull the bolt off the carrier, and with just the carrier with key, dry fit it into the upper receiver.  The sides of the key should not be binding on the upper track, and when the front of the carrier gets about a 1" from touching the barrel extension, the gas tube should cleanly enter the key.  If the sides of the key is binding in the upper track, you may have to lap the sides of the key to get the needed clearance.  If the gas tube is not correctly indexed with the key, then pull the hand gaurds to tweak the key over the center of the barrel to correct its index with the gas tube.

Next we need to check for gas leaks, being the gas tube to the FSB/gas block, the gas block/FSB to the barrel and even the key to the top of the carrier.

The quick way to check the front end, CLP at the tube to block/FSB, both ends of the FSB/gas block to the barrel, then a rubber tube on the end of the gas tube in the upper receiver to pressurize the gas tube to about 100lbs of air.   On the carrier, the same with holding the bolt inwards, CLP around the base of the key to the carrier, then charge the front of the key with 100lbs of air.   Hence none of these contact points should be leaking (with the exception of the gas tube to block, and only a slight bubble of out).

Lastly, the 10.5" barrel is ammo select as hell, due to short amount of bore after the barrel gas port.  To really check to make sure it not the ammo that is the problem, but the rig instead, XM-193 or PD-855 ammo should be your check ammo to begin with.  If it runs fine once cleaned/lubed correctly with it, then you can start to try some other ammo's to see if the gun will still run with them.  And yes, the 11.5" barrel is a much less an ammo selective barrel, due to the 1" more bore after gas port instead.