The gas system on the SKS, which allows it to extract almost flawlessly is most of the cause for its accuracy issues.
Considering what the accuracy requirements are for the rifle under stressful, field conditions, it's just fine.
The other issue with SKS rifles are mostly due to bore diameter variances. I have a Russian refurb with a bore diameter of .315 in. and a new in grease Chinese SKS with a . 309 bore.
The best shooting SKS I have is a Yugo M59, which has a .310 median bore diameter.