Squaring up a norinco receiver

[nemesisincanada]

Has anyone had experience with a Norinco receiver that has a non-square face to the barrel?
Has anyone attempted to square the face up before fitting a match barrel?
How have people with LRB receivers found it for being true?

 

[M14Doctor]

Never seen that before.
When installing match barrels, the barrel shoulder is prepped, NOT the receiver. On LRB receivers, the barrel shoulder on krieger barrels generally needs a 1 thou to 2thou undercut.
It is generally not adviseable to alter the receiver's torque shoulder face. If I were to discover an out of spec receiver such as you mention, it would become a paper weight and nothing more.