My bullet trail?

My bullet trail is on, but when i aim/spray with my AK or M4 the first few bullets show and then the bullet trail disappears and reappears 5 seconds later.
Even if i re-spawn the bullets never show when I shoot the wall and a few deaths later it comes back..and then disappears. My FPS and Pings are normal; does anyone know why it happens? Can i fix it? I've already tried re-logging but the same thing happens.