i've never shot the 7.62x39, but back in the day my 223 ak would tear the norinco brass in half- it would only eject the back half of it, leaving a brass tube in the chamber and a nice solid jam for the next round. Keep an eye on it for the first couple of mags.
Unless something has changed, the yellow-box Norinco is no longer imported (for years now) and any of it is collectible. It would be of value to cartridge collectors here & elsewhere. You may be able to get your investment back and then some if you check around with them before you shoot it all up (and it IS great ammo). This used to be sold for $88 a case SHIPPED before the Clintoons got into office and screwed everything up.
Last year I got 1000 rounds of Norinco yellow box and 800 rounds of German plastic core in blister packs, both in the original crates, from a guy on a jobsite. I gladly paid his asking price of $150 for all. He even helped me carry to my truck.
I have 3 wood crates of Norinco (White Box w/ Green Lettering) that was bought YEARS ago for $75/case. I've wondered what it was really worth for a long time. I went to a shoot a couple of years ago and was shooting it and was told not to shoot it (WTF?) because of it's value. People were actually giving me boxes of ammo to shoot because they didn't wanna see me shoot the stuff I had (again WTF?)... That was what it was bought for. It's supposed to be steel core but I've never checked to verify this. I know it's NOT corrosive though...