As discussed in the article What Blue Solution to Use I explain that it does not really matter what you use as long as it is corrosive, in the article I compare salt water with rust blue solution and end up with the same result.
However I still get people contacting me asking what solution I use as the one they use doesn't work. My advice to everyone on the topic is keep your solution simple. I have had people contact me because their firearm is turning an odd colour, when I ask what is in their rust blue solution, the number of ingredients is as long as your weekly grocery list.
Further advice to people is, if they are only going to do a single firearm or two, just use salt water. It is cheap, non toxic and does the job well. If you are going to be doing a lot of firearms, then yes, making your own solution is a good option.
Above is a picture of the chemicals and equipment you are going to need, they are listed below in roughly left to right order from above:
Note: While not shown it is recommended that a respirator be used.
The funnel, glass jar, gloves, eye protection, distilled water and the scale should all be easy to find. The rest as below:
The method of mixing these ingredients is fairly dangerous. The act of adding the iron to the acids produces a huge amount of gas, which if your not careful could overcome you. I mix the ingredients outside on a glass top table. Below are the steps to mix the ingredients to fill a 500ml bottle: