I have a Norinco 97 and its a third gen. It's been trouble free but the wood is crappy. Borrowed this from sassnet.
there is a general (incorrect) assumption that the generational changes can be figured out by the (3) starting numbers of each serial number.
(example): 998XXXX (1998/1999), 000XXXX (2000), 010XXXX (2001), 020XXXX (2002), 030XXXX (2003) and 040XXXX (2004). All these numbers tell you is what year the frame was cast, milled and serial numbered.
A 1st and 2nd. generation, yes, but subsequent generational changes were so numerous, that they were lumped together right in the middle of production, and this started in 2001 with serial numbers starting 010XXXX (7 digits), and continued until 0103200 (approx) as the 3rd. generation of modifications and improvements.
The 4th generation started just after those numbers and included (among other things) a major change to American Walnut stocks from Missouri.
So, if you have a serial number in the 0104500 range, it will have pretty nice walnut stocks, an upgraded carrier (at the cam pivot circle), an improved left extractor and a narrower, lightened firing pin (to prevent breakage from dry firing).
The 5th generation is far easier to identify because the pistol grip on the walnut buttstocks was changed to the (E) model flat (not rounded) design of the original (E) model Winchester 97.
Also, all "Trench Guns" are of the 5th generation and are actually pretty good guns, as the metallurgical tolerances were much more closely watched, and also, these guns had some more internal changes, to include another change to the firing pin, (to make it safer), and upgrade to the ejector, right extractor and an improved and much lighter and thinner mainspring.
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