Check the barrel lock up. Some Norcs have a loose bushing/barrel fit, and some have a loose barrel link/slide stop pin fit. If both happens to the same gun, the barrel could be very loose and bullets can fly everywhere.
I find that Norinco uses slightly under sized parts to ensure reliability. Sometimes the problem can be easily solved by changing to "over-sized" parts.
I did that to my NP-29, and saw improvements. Now I am using that NP-29 as my workhorse IPSC gun.