Chinese Factory Code 916

Greetings To All,
I have a question concerning Chinese Fasctory Code 916. Does anyone know anything about this factory - like if it is somehow associated with Factory 26 in some way? The reason why I'm asking is because I'm really impressed with the quality of workmanship concerning this gun and I'm wondering if it is related somehow to this Factory 26 which I've heard so much about. I'm thinking that it must have been manufactured sometime around 1965 give or take a year. It is in serial number range 1,5xx,xxx but it exhibits some interesting qualities that makes it difficult to date. It has for instance a spike bayo, a one-piece gas tube, a short barrel nut, a side swivel, lightening cuts on the bolt, and a milled receiver but it also looks like it has a chrome chamber which I thought was a later feature and it also has a stamped trigger guard. I have heard so much about Factory 26 and the quality of markmanship there but I have never heard of Factory 916 and I can't help but wonder if these two factories are possibly related - based simply upon the quality of workmanship of my gun. If anyone has any information that would provide me with some insight as to the history of where my gun was made, I would be most grateful in hearing what they have to say. I look forward to receiving your replies. Thanks in anticipation.

The first Chinese SKS rifles were produced at Factory /26\ the Jianshe Arsenal starting somewhere around 1956,the /26\ rifles are the only ones that can be reliably dated by the serial #. Factory Code 916 is just another one of the many arsenals that produced the SKS rifle in China and there is no reliably dating system for the other arsenals.

A couple things you can look for in general,the spike bayo appeared around 1966 to the end of production,around 1970 they started using stamped steel trigger guards instead of all milled. Up to around 1970 the Chinese use either a long and later a short barrel lug to hold the barrel to the receiver,in some factory rifle after 1970 they pinned the barrel to the receive and did away with the barrel lug.

My factory /26\ rifle was made in 1966,has the short barrel luge,all milled parts and the spike bayo.