We here tend to think like the westerners we are. The Chinese don't think like us or produce weapons in the manner we do. Everything there is state run and controlled ESPECIALLY weapons production. There are no private "commercial" producers of military rifles in China all are state run and state approved or owned by the PLA and various high ranking generals. There are differences though in the plants which produce weapons. Some are very large, and some are very small and many are medium in size. They are spread all over China. So there are bound to be some very minor differences in the weapons produced. Back when SKS rifles were being sold in the U.S. there were many importers importing rifles from China. The Chinese sold what they had in storage, and when there was a specific request for a different variation ( short barreled "para trooper" ) Ect. they simply modified the rifles they had in storage to meet the orders.
So although the rifles were modified for commercial sale to importers in the U.S. the rifles came from military stockpiles and were modified in military facilities.
So here is the question if the Chinese take a SKS rifle which is in military storage and send it to a state run armory to have the barrel shortened for sale in the U.S. does this make the rifle "commercially" produced. IMHO the answer is no.
I never met a gun I didn't like!
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