Mk16 and Mk17 variants do not vary in accuracy or range, only in weight. This also gives the Mk16 very low accuracy compared to the other 5.56mm weapons; it is very difficult to consistently hit targets beyond 400m even with high-powered sights with variable zero
Edit: Nvm the Mk16/17 part. Instead, perhaps a review should be done on weapon accuracy values for some weapons. The Mk17 CQC, M4A1, G36K (especially) seem to be too accurate compared to similar weapons (though admittedly there isn't much to compare the mk17 to). This is a relatively minor problem and should not be allowed to delay the next update or detract significant resources from other issues if it comes to it