Rusty Gun Bluing

Can you fix this old rusty gun? This is a question many customers have asked me. "Of course I can. The gun will look like new again," I reply, because it’s true. There are many types of refinishing possible and bluing is always popular. The method most professionals use is called "hot rust blue" and in the lines below I will show you how it is done in stages.

The first step is to examine and inspect the firearm to be blued for damages, like a loose rib, dents and bulges in the barrel or cracks and splits in the stock, at the forearm and the like. Then we check for general function to make sure the gun works. The trigger, safety and workings of the action are tested, ideally with with live rounds in our range or in a specially designed firing pit that are available to the trade for those who don’t have the luxury of a range behind their gunsmith shop.

If there are there any problems in either of these initial stages of inspection and function, then we will not proceed with the bluing unless we have afix for the discovered problems. Of course, we will have advised the customer about the extra cost of the repairs which in most instances must be done before the bluing. Now we are going to proceed with the disassembly of the firearm. Do I need to remind you to wear your safety glasses? They should be on before you even have touched that gun.

If we know the particular firearm, well then it only takes a few minutes to disassemble it after properly clearing it. If not then we look to our assembly/disassembly publications (books, manufacturer manuals, American Gunsmith, etc.) as they are very handy. If the firearm to be blued is not addressed in something available and we are not familiar with it then we use a digital camera to keep an on-going record. Take several pictures of every step Any needed repair work must be addressed before bluing.

Once inspected, clean the parts thoroughly. More importantly, good bluing depends on good polishing and sparkly-clean parts. This prep work is critical! as you go along with the disassembly to have a reference when ready to reassemble. All right, we now have completed the disassembly and we have all the pieces on our bench. The next step is called preparation. Our objective with this phase is to prepare the metal for the bluing. This step is very important.

We must do our best because any mistakes here will show later as flaws on the blued gun. First thing is to clean all parts from dirt, crust, grease, oil and whatever else has been collected on them over the years. Not everyone keeps his gun nice a clean as he or she should and, obviously, any firearm needing to be refinished has seen much use and will have the attendant wear and tear. We can use kerosene for this initial cleaning

Polished bluing requires buffing, typically done with a buffer like the Baldor (right). Lacking this equipment the only other option is to polish by hand. However it gets done, polishing is key to a good bluing job. along with a bristle brush or mild steel wool suitable for gun work. Follow this up with Simple Green or a similar cleaner. If the customer wants a matte blue finish, then the pieces to be blued go to the bi-blast cabinet. If he wants a polished blue then we have to use our buffer and belt sander.

If we don’t have any of the above power tools to do what is called "power polishing", our only option is to polish by hand. If there is any pitting on the freshly cleaned and polished surfaces it must be removed with afi le via draw filing, removing just enough metal to erase traces of the corrosion. Of course, this will leave filing marks that need to be removed. Using a polishing cloth, start with the closest grit that will give an even surface finish, such as 180 or 240 aluminum oxide grit.

The goal here is very simple. We must remove all of the previous marks done by the courser cloth. This is done much better and easier by changing (rotating) the direction we polish every time we change grit. For example, we start with #180 cloth to polish the length of the metal piece to remove marks from draw filing. When we switch to the #240 cloth we polish at we can see as we precede. The metal will "speak" to us.

For even better results and to extend the life of the oxide cloth it should be lubricated with a light weight oil. Regular gun oil is good for this. I’ll say it again. Good polishing is very important! All edges, corners, and fl at areas must be kept clean and sharp and all previous sanding marks must be removed. Good bluing can never cover a poor polishing job! Now that we have all the pieces polished to a high luster, it is time to fi re up our bluing tanks. While waiting, we start to clean the parts to be blued.

I mean really, sparkly clean. The parts must be degreased thoroughly with acetone, with great emphasis in the ribs, tight areas, screw holes and every tiny nook and cranny, externally and internally. When completed, we cannot touch the parts any more with our bare hands. Any oil from our skin or finger prints left on the parts will show later as "shades", will be just plain white as they will not blue. Use hangers for all handling after completing degreasing.

When the thermometers in the bluing tank show the right temperature, somewhere between 275 and 290 degrees Fahrenheit, we have a nice boiling solution to put the well prepared parts in. Some guns will blue in as little as 5 minutes, some in 20 minutes, and others will take a little longer. This depends on the type of steel.

When the parts are blued we take them out of the bluing tank and put them in the hot boiling water tank for two minutes and then transfer immediately to cold water tank to cool the parts for one minute. From there we immerse them in to the water-displacing oil tank and hang them to drip off the excess oil. Once the excess oil has dripped away, we clean the parts from the rust preservative oil and we give them a liberal coat of RIG grease. Set the parts aside for two or three days in a dry clean area.

The next step is to reassemble the gun. We must take great care not to mar the surface in any way and avoid making marks or scratches on the bluing. After the gun has put together it is time to test it for functioning again. After a successful test firing, clean the bore again, lubricate all moving parts and lightly coat the metal surface with gun oil. The last thing we do is pick up the phone and tell our costumer his "new" gun is ready! If we did our best, he will be a very happy shooter. Good luck to all. AG