Hm... I didn't know. I just assumed that if using a pistol crossmod, anything you have to hold down the trigger for will cause it to NOT be auto. Since I made my default pistol into a Scorpion and I held down the trigger, it still fired like a pistol. No auto. So I assumed the rest for full-auto weapons. But the flamethrower is like an 8 round burst so I thought that would be the only option. :/