Here's the pistol. Waiting on the SBR form to come back to put the rifle stock on:



Here's what it's doing to the bullets/brass:









And this is what it looks like when the jam happens:







Here's the feed ramp area:












Specs on the build are:
Lower is a Sharps, bought 4 years ago when the gun boom went bust. I've build several ARs on these, they work fine.
Lower kit is PSA
Pistol tube is PSA
Magpul ASAP
Magpul pistol grip
Magpul ARG (I've got an ATF letter somewhere that says this is OK on pistols so please stay on topic)
Magpul BAD
MI first gen carbine free float handguard
Upper is AR Stoner
BCG is AR stoner
Barrel is Alpha Shooting Sports 10.5" Stainless with Pistol gas port
Gas block is YHM low profile
Gas tube is Novesky.

I know, it's a real mutt, but I've been at the mercy of what's available.
Note: this happened with two different magazines.


Now I've been told that I need to polish the Bolt carrier's bearing surfaces to take the fresh parkerizing off and will do that, but I don't think that would cause the above issue. I've also been shown that there is no radius on the leading edge of the barrel going into the chamber and that is where the brass is hanging up. Supposedly this is not a problem with the small .223 but can be with the .308.

Picture showing lack of radius:


I've looked at my other two 300BLK ARs and sure enough, there is a nice bevel on that leading edge.


OK, do ya'll concur that this sharp edge is causing my problem? If so how would ya'll suggest fixing it? I was thinking of a precision drill bit chucked up into the lathe to break the edge. Then sandpaper and steel wool.

Any other ideas? Thanks