I have had a number of students show up on courses with this stuff and found it to be very inconsistent. Blown primers, gas erosion on bolts, split cases, key-holing, excessive fouling, failure to lock and dud rounds. I've since included a note to not bring this for courses where they use our rifles. I brought home a dozen boxes from the last course to check them out. I had never looked at the different products.
I pulled 20 rounds from a box picked at random and checked them out. The case head stamp is CJ 93. No lot numbers were on the yellow box which was labeled: 223 Remington.
First I weighed every cartridge on a Hornady electronic scale and measured COAL and bullet diameter just forward of the cannelure.
Next I used a Wilson Case Gauge to measure cartridge headspace.
Then I pulled the rounds using a Kinetic puller so as not to swage the bullet. I weighed the charge, the projectile and measure the diameter behind the cannelure.
The bullets had sealant applied and were standard FMJ with an exposed core at the base. The propellant was much flatter than standard St Marks ball.
I checked every projectile with a magnet and none were attracted.
This particular box compared favourably with M193 or AE that I have checked, except the projectiles are undersized.
COAL was fairly inconsistent. 3 rounds were .001 over max chamber headspace size and would likely have chambered with a tiny amount of crush up.
Overall weight was also not bad, varying from 179.5 gr to 182.2 gr.
The bullets at first appeared to be VERY undersized - likely due to an aggressive crimp. Measuring the bullets AFTER pulling showed that while they were undersized, it was only by about 1-2 /1000". I could not find a single round in my loading bench that measured smaller than .224, yet only one Norinco round was that large (#18). Bullet weight averaged 55 gr, but varied from 54.6 to 55.7 gr. I suspect this would affect accuracy.
The charge weight was quite good except one round that was .5 gr low.
It would be nice to compare these measurements across different lots and with a bigger sample, but I thought it was interesting anyway.
I'm going to take another box and shoot some chrony data through a barrel I don't care all that much about after x-mas.