I am getting close.. just been spinning my wheels on my last print. previous 4 builds worked great, last 2 prints (with new print material) and it became less reliable. This just means I need to order some of the good print material to keep the reliability of the part.
Interesting enough empty shell casing allowed me to see the issue due to its expanded neck size.
So so far I've been testing using PPU 5.56 (bullet), American Eagle M163 (bullet), Lapua reload (bullet), Wolf 223 (brass only), Lake City 5.56 (brass only), Frontier 223 (brass only) for test feeding. Of course this doesn't replace live fire as we all know that's where issues pop up.