Yes indeed, I have used it on both steel and alum parts, and am very pleased. It is important to do a very spiffy cleaning job on the parts, and I always vibrate finish them with medium grit abrasive to give the surface some "tooth" to better accept the paint. The finish is not unlike that of the Rem 870 Express shotguns, and seems to be very servicable in use. I use it for small runs of parts, rather than the more expensive (and quite frankly better) powder coating. If I have enough parts to make it worthwhile, I'll opt for powder coat, but that starts at $50 minimum and goes up from there. So the Guncoat gets used often...