Hi guys,
I understand that PolyTech and Norinco are just export companies. They order rifles from factories. Norinco is a government export company and civilian in nature. Norinco has been in existence from the ear China was sponsoring national liberation movement all over Asian and Africa (60s-70s). Polytech was new, set up by the sons of high ranking officials (e.g. Marshal He Long's son) in 1980s. PolyTech was an PLA company (People's Liberation Army). Because the special status of PolyTech, they were less subject to central government control and were more clever business people. They set up much higher QA standard and aimed at quality rather lower prices. In 1990, central government forbid PLA companies to do business in civilian markets, so PolyTech became an independent company (by name). Their US presence ceased after they got entrapped by FBI. They sent 2000 full auto AK47 to (they believe) Bosnia en route Oakland, CA. The container was downloaded by FBI and the whole event was used as evidence that Chinese government tried to send full auto AKs into the US. Several PolyTech officers were indicted but never presecuted, but US government informed them to leave US before the case was brought up. After that, PolyTech ceased its US business that was FBI's original intention.
PolyTech and Norinco buy guns from factories controlled by government. PolyTech bought more guns from factory 386 (in Fu-Jian Province). Norince bought more from factory 366 (triangled 66) in Heilongjiang province.
Facotry 66's export AKs had much rougher finish than their military contract FA rifles which I had used in my youth. The military AK I used was from factory 66; similar to the Legeng in that it was milled, but it has a folding bayonet and, of course, FA.
Legend were made in factory 386, using milled receivers which had been abandoned at the time for PLA contract. They filled the Legend order using machineries already put away in storage.