Direct thread rifle silencers are great for full auto and normal semi auto use. The issue is when people don't buy the right type of direct thread silencer. If it doesn't have wrench flats or if it doesn't have the SIG 25 deg taper interface when hand tightening, then it's likely it'll come unscrewed during use. Use a silencer with wrench flats or use the SIG 25 deg taper interface and that problem goes away entirely.