Bryant is right.
Muzzle flash is caused by unburned powder burning once the bullet has left the barrel. If you use a load where the powder is completely burned by the time the bullet leaves the barrel, there shouldn't be a muzzle flash.
In fact, in ported guns, the object is to force the expanding gas from the burning/burned powder through the ports in the compensator and keep the muzzle down. The best way is to use a load that completely burns the powder so that you don't end up "wasting" burning powder outside the compensator.
Muzzle flash is caused by unburned powder burning once the bullet has left the barrel. If you use a load where the powder is completely burned by the time the bullet leaves the barrel, there shouldn't be a muzzle flash.
In fact, in ported guns, the object is to force the expanding gas from the burning/burned powder through the ports in the compensator and keep the muzzle down. The best way is to use a load that completely burns the powder so that you don't end up "wasting" burning powder outside the compensator.