As KMS alluded to earlier, some of the post-94 "Egyptian" (use this term
loosely to describe them) AKMs in the sporterized form were assembled from disassembled chinese AKs.
A huge import of Chinese AKs were in warehouses when Bush Sr.
****ed the gun import industry. As a result of this unfavorable situation, they were all demilled into parts kits. Some were built onto Maadi receivers (I think an importer ordered a bunch or some shit) and thus, you get the miserable red headed bastard child of a Chinese and an Egyptian.
Talk about f'd, eh? Well, the reason why they sucked is that the assemblers were numb nuts. All the barrel components were pressed on by US gun smiths who don't know their head from their ass, or just didn't care. I'm guessing a shitty finish was put on the receiver post build, hence the gritty feeling.
Also- chinese barrel components are meant to go on Chinese Milled or stamped rifles - their barrel journal profiles are one in the same. Milled AK barrel components are designed for a slightly beefier journals. So they had to sleeve the components in order to fit the egyptian barrels (if they used them, which I believe they did... otherwise they'd have had to modify the chinese barrel trunnions to fit maadi AKM receivers - receiver sheet metal thickness is different between chicoms stamped AKs and AKMs.) This would make the sight and gas blocks look weird as hell. I know most MISRs are Chicom trunnioned barrels in Egyptian receivers... they have the Chinese rivet pattern as well as the oblong Maadi magazine dimple, as can be seen here:
Classic Chicom rivet pattern, signature Maadi oblong mag dimple. Signature deep Egyptian spot welds. Mind. Is. Blown.
SAM-7's are nice. Milled AKs run pretty damn smooth, that's for sure.