Screwdrivers may or may not be the right steel for the job. They are meant for toughness. Assuming one is simple high carbon steel, they are good for the purpose because the shaping is practically done. It is wrong to cold bend steel that is to be used for tools, whether it is annealed or not.
I heat them with a propane torch to bright orange then quickly bend them using a vise or pliers. Depending on where it will be used, I make the "foot" from 1/2" long (for leveling tang or lock inlets) to 2" long (for barrel channels). Re-heat and get the second bend in to make the dogleg. Make sure that when the foot is flat on a wood surface, the handle is slightly tilted upwards toward the butt of the handle. Now heat the foot but no more to bright orange and quench in transmission fluid while stirring around. Do it outside or you will hear about it. Check to see it got glass hard by trying it with a new file. Polish everything up. You can use an old brick to do this if you want to be old-timey and cheap (they go together). Next I heat the chisel with a propane torch focusing on the last bend and watch the tempering colors run toward the edge. Go slow and easy, sweep the flame, don't hold it too close. When you get nice long color transitions you're doing it at the right rate. When a dark straw reaches the tip, plunge in the transmission fluid again. Sharpen and use.
