That has not been my experience. I've been able break the Rocksett on my Glock front sights when changing from tritium to fiber optic with just the hex nut driver. Similarly I've never needed to heat any parts to remove set screws from gas blocks or even muzzle devices when the Rocksett is applied in reasonable quantity. Since Rocksett withstands temperatures up to 1500 or even 2015 degrees F per their product description, I wouldn't expect a torch to be very helpful unless applied to the extent that it could also cause damage to the sights or slide.