ALL stamped military AKs, except the Yugo and Chinese, use 1mm receivers. 1.6mm receivers are an US concept used to probably save money (more common thickness here) or to use in marketing.
Wrong and wrong, Lots of misinformation here guys. There are plenty of AKM based Yugos that are 1mm and non bulged, Also all of the stamped Bulgarian 7.62x39 guns use thicker 1.5mm or so recievors. The Chinese stamped guns are around 1.3-1.5mm or so as well. The SSR-85C is made from Hungarian Type 3 parts guns that are no longer able to be imported with the barrel intact, and therefor made into stamped guns in Bulgaria with new made or surplussed stamped bulgarian 7.62x39 front and rear trunions. They use the same thicker recievor (1.5mm or so) that the other Bulgarian 7.62 rifles used, just of a slightly diffrent die design than the military guns (dimples and stuff)
There are also plenty of Saigas in the larger rifle and shotgun calibers with 1.6mm recieviors.
In short, AKM based (usually 1.0 mm) guns from Bulgaria and China are thicker, RPK based guns from Yugoslavia (with bulged front trunions) are the regular thicker RPK type 1.6mm, Saigas are AKM based untill the front trunion is bulged, then they are thicker. Milled recievor guns do not even fit in here, they are thicker and do not use sheet metal for the recievor, and are not measured in thickness, as they are diffrent thickness depending on where you measure and not standardised, much stronger all around than even 1.6mm stapmed recieviors when heat treated propperly. All military are either AKM based 1mm's or RPK based 1.6mm's but for China and Bulgaria, which did some funny stuff. And the large rifle and shotgun caliber saigas are tweaked RPK based recievors. The PSL is also a tweaked RPK based recievor. Yugo M76 is Milled.
If its a US built parts gun, then a builder can do whatever they want, including using the thicker Bulgarian type recievors and just shaving the trunions a little bit and building any AKM based gun on it. (Romanain, Polish...) But this will be very obviously specified.
That pretty much covers the whole current AK platform.