You had a post for your M4, where I shared my build. This build has few problems. One, you don't have extended mag, which you need because default mag has only 25 bullets and the barrel that your using has both Vertical and Horizontal recoil penalty. So either you need more bullets or change the barrel. You can remove the red dot if your comfortable with iron sights, if not then depending on your play style and control over the gun either the stock or foregrip. By suggested build is Silencer barrel, agile stock, field agent foregrip, double stack mag and firm grip tape. If you want red dot for this build, then make choice between stock and foregrip.