One of the joys of gun ownership is the ability to personalize your firearm. For some this means changing out sites, recoil springs, and other temporary additions that change the mechanics of the gun. For others there are more permanent changes such as stippling and slide porting which cannot be undone and, if done improperly, damage the firearm. Then there are little cosmetic changes that are pleasing to the eye of the beholder that can do not affect the performance of the gun one bit, but do put a smile on one's face.
That's where adding color to the etched roll marks of your XD would fall.
This can really turn a ho-hum black Croatian hog leg into the bell of the ball. Its been discussed a few times on our forum and some of our members really set their guns off with just a little bit of war paint.
Red filled XDM by member Doctor7474
First, remove your magazine, rack your slide (three times), and both visibly and physically check for any brass or ammo. Remove said brass and ammo from the room before you start your smithy work. Can't stress this enough. I have a good friend who has a bullet hole through the back of a folding chair in his workshop after not following this practice. Good thing it was only a chair.
No matter which method you use to add color to your gun, you want to start with a clean surface. This means take your metal surfaces and clean them with mineral spirits, rubbing alcohol, or both. Stay away from oil-based solvents and anything that is advertised as a lubricant as this will leave a thin coat of residue behind.
Then make sure its clean and dry. It is best to wear latex or otherwise vinyl/rubber gloves to help keep the grease from your fingers off the gun while you are working on it, and likewise paint/chemicals off your fingers. On another safety tip, use this stuff in a ventilated area. Huffing fumes is bad, m'kay.
Now let us look at some of the different techniques.
When going to pain your gun, you are looking for a good quality enamel based paint that is going to adhere to metal and remain on your weapon for a good bit. Stay away from airbrush and latex. Stay away from water bases. A good, inexpensive paint to use is Testors model paint markers or those little bottles of Testors enamel model paint. Most of you remember this stuff from when you were a kid and you can still get it at most hobby shops for next to nothing.
Brownells even sells what is called LaquerStik for this very purpose, and is comparable to a Testor's paint marker.
Application of raw paint if you aren't using a marker can be done with an extra fine pointed brush, toothpick, razor blade or a needle. You will want to use some sort of solvent to strip away excess when you are done. However, if you don't mind getting your fingers dirty (remember that glove comment above?) you can always just swipe the area with your finger after you apply the paint.
Jaymn2589 takes on his XD, going for the slide etchings on his gun with Testors model pain using a needle method and Hoppes No. 9 solvent to remove the excess.
With a safe and prepped gun, take your desired color of good old wax crayon and color into the etched area that you want to fill with color. Now remember this is wax, so you need to press that stuff in there evenly across the roll mark to make sure it looks good. This is some of the easiest methods to add color to your gun and to clean the excess off, just wipe with a rag. To strip the wax out if you are tired of it, you need to heat it up with a hairdryer or warm air blower, and then give it a good scrub with a plastic toothed brush.
The melonite coating on your XD slide is pretty tough to beat up, but there is no reason to take a wire brush to this if you don't have too.
Vash241987 filling the engravings on his XDM-9 with a crayon. Note he uses a hairdryer for the warm up and a cardboard scraper.
Nail polish method
With a safe and prepped gun, you can simply take your desired color of nail polish and swipe it on, then after it dries dab it up with some non-acetone nail polish remover on a rag or Q-tips. Be gentle or you will seep it into the roll marks and defeat your whole goal.
Avid Shooters doing a simple overview of both the nail polish and crayon methods. Yes, we know he is using Glocks, but just close your mind to the dark side, they do not have cookies.
To keep your color filled in the longest, you may want to consider using a hand glaze that you dab on right after your polish, paint or wax is dry.
Again, this stuff is not for everyone, but if you like it, knock yourself out.