A warning about connections / transfers using Air China
 

If you are connecting between two national flights in China make double sure you are buying one ticket and not two. Otherwise they will make you claim your luggage at the connecting airport, go outside and check back in. You cannot check in for both flights at the departing airport.

Example: I recently flew Changchun-Beijing-Shanghai. Even though I had the booking confirmation and all other info on hand, the Changchun station was unable to see my Shanghai flight. (Truth be told I don't think they tried very hard either.) When I previously flew the inverted route on one single ticket, connecting in Beijing was no problem at all.

Hope this helps one or another person here avoid missing their connecting flights.

This is the way it works in China. Having your luggage checked through is pretty rare.

Actually, I think this is a pretty good warning to make, and I don't think is specifically limited to Air China. Most travelers inside China fly point-to-point and only a minority need connecting flights. So nearly everybody takes it for granted they will pick up luggage after each flight. If you need to fly two domestic segments with a connection point and know this upfront, definitely get it all on one ticket if you don't want to deal with luggage at the intermediate point, and preferably on one airline.

From any Chinese airline's perspective, they don't want any responsibility added to what is on the ticket you purchased. If you purchased two separate tickets to form a sequence, then it's two separate contracts. the airline wants to deliver you and luggage from point A to point B then essentially close out that first ticket contract, and not complicate things by trying to link tickets (and by extension, luggage transfers from point B to point C).

That puts more responsibility on the passenger but given the characteristics of the domestic market in China, it's probably better to keep it this way for now. Also, most Chinese passengers would rather ensure (via bag pickup) that their luggage made it as far as they did...and they are used to doing more manually. The extra convenience of being able to link separate tickets and check bags through is overshadowed by the lack of trust between airlines and passengers.

it is possible to get checked through (I managed to get this done today) but you have to make sure to tell the travel agent two, three times to really only purchase one ticket.

I think it depends on the airport and the airline. And the knowledge of who is checking you in. In general f you are going through an airline's main hub, you can usually through check luggage.

On the other hand, a few months back I was connecting on Air China through Xian (only a focus city and not a hub) on one PNR and when checking in at PVG they said they do not offer luggage through check there yet. I had to claim and recheck my luggage. Though I got both boarding passes in PVG they reissued the connecting BP in Xian to make sure I could use the priority security lane. I think this also happened in Chongqing.