Absolutely.  Much of the foreign surplus is made on old, worn, ill-maintained equipment with indifferent "quality control".  Then factor in its age and how it was stored over the years, and it doesn't take too much to figure out that accuracy is going to be lacking.  Finally, understand that M193-spec loads are optimized for velocity, not for accuracy, and you'll usually find that lighter loads tend to give more accuracy than those pushing the pressure envelope.

-Troy