gunsaholic
CGN Ultra frequent flyer
- Location
- Winnipeg, Manitoba
Okay, on another thread the question was asked about how I slow rust blue. I decided I'd start a new thread so as not to hijack the other. First I want to say I am by no means an expert and I have only done barrels for myself on guns I have restored. Everyone has their own techniques and tricks. This is the way I do it and it works for me. Others may feel free to add their own tricks/methods.
I start by removing all old grease, dirt and oil from any screw holes etc. Then I remove the old bluing. This I do usually starting with 220 grit emery cloth. If there is deeper pitting I will start with a coarser grit. Some deep marks/pits will have to be draw filed out. However, you can only remove so much metal so there are times when you cannot remove a complete pit or gouge. Be careful around any lettering. You don't want to remove the lettering if at all possible. I sand lengthwise to the barrel and work my way up to finer grit paper. I usually don't go beyond 400 grit and sometimes not beyond 320 grit. There are those that go finer than 400 but depending on barrel composition, the rust bluing solution works a bit better if it has a "rougher surface" to bite. Also, the more cycles that are done tend to hide imperfections. Some people take barrels to a wire wheel but I do it by hand. When the barrels are sanded to my liking, I degrease with alcohol or acetone. You want to make sure you wear gloves at this point and do not touch the barrel with the bare hands from here on in. After degreasing, I apply the rust bluing solution with cotton swabs. Have the swab saturated but not ringing wet. Make the necessary passes to coat the barrel. If you miss a spot do not go over it or you will get blotching or streaking. Any missed areas can be gone over in subsequent cycles. The first coat is appllied and left to sit for an hour or two, then a second coat is applied directly over the first coat. This is the only time you will apply a second coat over the first coat. The barrel is then left to form a nice uniform coat of rust. How long that takes depends on the humidity. I don't have high humidity in my house so I bought one of those wooden ammo crates from Princess Auto. I put a hook at one end to hang the barrel. I then hang a wet rag on each side. Putting in a lamp may also help with the humidity. I find with this I usually let sit for about 24 hours but that will vary. When the barrel has rusted it goes into the boiling tank. Some say you need distilled water but I just use tap water and it has worked fine. Guess it depends what is in your water. I bought a stainless steel boiling tank from Canada Ammo. All I have for a heat source is my wife's oven. I lay it across 2 elements and bring the water to a boil. I'd like it hotter but it works. I only put in enough water that is needed to keep the barrels covered. Once it is boiling, I place the barrels in it for about 20 minutes. I suspend the barrels from a rod running through the barrels. Some plug the bores with stoppers. I used to but no longer do. With boiling water, it flash dries pretty quick plus I run a dry patch through as soon as they are done boiling. I have had no rust yet in the bores. Which reminds me--only apply the bluing solution to the area you want blued!! The rust will form to black oxide when boiled. Once cooled down, you have to card off this black residue. Some use a carding wheel. I just do it by hand with 0000 degreased steel wool. You want to remove all the "black soot" but don't scrub so hard as to remove the bluing. When the carding is complete you degrease and start the process all over again. And remember, no bare hands. The first 2 or 3 applications will look as though not much is happening but then it will really start to take on the bluing. Subsequent applications may not appear as rusty as the first few times. When you have done as many cycles to achieve the depth you want, give the barrels a scrub down with a water/baking soda mix to stop the chemical reaction. I then give the barrels a coat of heavy motor oil and let sit 24 hours. Sometimes I heat the barrels with a heat gun before applying the oil. Don't know if it makes a real difference or not. I then wipe that off and apply whatever oil that normally is put on. The bluing will turn a fair bit darker when the oil is applied. If you are doing barrels on a double barrel, you have to drill vent holes in the bottom rib. The space between the ribs will have to be flushed out afterward.
There are a few makers of the rust bluing solution. I have gotten mine from Brownells so I never looked for it in Canada. There are also formulas on the net to make your own solution.
As mentioned, this is the way I do it and it has worked for me. Anyone may feel free to add as I likely forgot something.
I start by removing all old grease, dirt and oil from any screw holes etc. Then I remove the old bluing. This I do usually starting with 220 grit emery cloth. If there is deeper pitting I will start with a coarser grit. Some deep marks/pits will have to be draw filed out. However, you can only remove so much metal so there are times when you cannot remove a complete pit or gouge. Be careful around any lettering. You don't want to remove the lettering if at all possible. I sand lengthwise to the barrel and work my way up to finer grit paper. I usually don't go beyond 400 grit and sometimes not beyond 320 grit. There are those that go finer than 400 but depending on barrel composition, the rust bluing solution works a bit better if it has a "rougher surface" to bite. Also, the more cycles that are done tend to hide imperfections. Some people take barrels to a wire wheel but I do it by hand. When the barrels are sanded to my liking, I degrease with alcohol or acetone. You want to make sure you wear gloves at this point and do not touch the barrel with the bare hands from here on in. After degreasing, I apply the rust bluing solution with cotton swabs. Have the swab saturated but not ringing wet. Make the necessary passes to coat the barrel. If you miss a spot do not go over it or you will get blotching or streaking. Any missed areas can be gone over in subsequent cycles. The first coat is appllied and left to sit for an hour or two, then a second coat is applied directly over the first coat. This is the only time you will apply a second coat over the first coat. The barrel is then left to form a nice uniform coat of rust. How long that takes depends on the humidity. I don't have high humidity in my house so I bought one of those wooden ammo crates from Princess Auto. I put a hook at one end to hang the barrel. I then hang a wet rag on each side. Putting in a lamp may also help with the humidity. I find with this I usually let sit for about 24 hours but that will vary. When the barrel has rusted it goes into the boiling tank. Some say you need distilled water but I just use tap water and it has worked fine. Guess it depends what is in your water. I bought a stainless steel boiling tank from Canada Ammo. All I have for a heat source is my wife's oven. I lay it across 2 elements and bring the water to a boil. I'd like it hotter but it works. I only put in enough water that is needed to keep the barrels covered. Once it is boiling, I place the barrels in it for about 20 minutes. I suspend the barrels from a rod running through the barrels. Some plug the bores with stoppers. I used to but no longer do. With boiling water, it flash dries pretty quick plus I run a dry patch through as soon as they are done boiling. I have had no rust yet in the bores. Which reminds me--only apply the bluing solution to the area you want blued!! The rust will form to black oxide when boiled. Once cooled down, you have to card off this black residue. Some use a carding wheel. I just do it by hand with 0000 degreased steel wool. You want to remove all the "black soot" but don't scrub so hard as to remove the bluing. When the carding is complete you degrease and start the process all over again. And remember, no bare hands. The first 2 or 3 applications will look as though not much is happening but then it will really start to take on the bluing. Subsequent applications may not appear as rusty as the first few times. When you have done as many cycles to achieve the depth you want, give the barrels a scrub down with a water/baking soda mix to stop the chemical reaction. I then give the barrels a coat of heavy motor oil and let sit 24 hours. Sometimes I heat the barrels with a heat gun before applying the oil. Don't know if it makes a real difference or not. I then wipe that off and apply whatever oil that normally is put on. The bluing will turn a fair bit darker when the oil is applied. If you are doing barrels on a double barrel, you have to drill vent holes in the bottom rib. The space between the ribs will have to be flushed out afterward.
There are a few makers of the rust bluing solution. I have gotten mine from Brownells so I never looked for it in Canada. There are also formulas on the net to make your own solution.
As mentioned, this is the way I do it and it has worked for me. Anyone may feel free to add as I likely forgot something.
Last edited:
