I found this a while back and just relocated it and though some here might find this interesting
Instructions for Browning Gun Barrels
From the British General Regulations for the Army dtd 1 January 1822
The following Instructions, which have been prepared by the Board of .Ordnance for Browning Gun-Barrels, and for repairing and retaining the Brown upon the Barrels, are annexed for the Information of the Officers Commanding Regiments, Troops, and Companies.
The following Ingredients,
Nitric Acid -- 1 ounce
Sweet Spirit of Nitre -- 1 ditto
Spirits of Wine -- 1 ditto
Blue Vitriol -- 2 ditto
Tincture of Steel -- 1 ditto
Are to be mixed together, the Vitriol having been previously . dissolved in a sufficient quantity of water to make, with the other ingredients, one quart of mixture.
Previous to commencing the operation of Browning the barrel, it is necessary that it be well cleaned from all greasiness and other impurities, and that a plug of wood be put into its muzzle, and the vent well stopped; the mixture is then to be applied with a clean sponge or rag, taking Clare that every part of the Barrel be covered with the mixture, which must then be exposed to the air for twenty four hours, after which exposure the Barrel must be rubbed with a hard brush and rag, to remove the oxide from the surface. This operation must be performed a' second and third time (if necessary), by which the Barrel will be made of a perfectly brown colour: it must then be carefully brushed and wiped, and immersed in boiling water, in which a small quantity of alkaline matter has been put, in. order that the action of the Acid upon the Barrel may be destroyed, and the impregnation of the water by the Acid neutralized.
The Barrel, when taken from the Water, must, after being perfectly dry, be rubbed smooth with a burnisher of hard wood, and then heated to about the temperature of boiling water; it then will be ready to receive a varnish made of the following materials:
Spirits of Wine -- 1 Quart
Dragon's Blood powder -- 3 Drams
Shellac bruised -- 1 Ounce
and after the 'Varnish is perfectly dry upon the Barrel, it must be rubbed with the burnisher to give it a smooth and glossy appearance.
The Barrel, with the Socket and Neck of the Bayonet . only, are to be Browned; they should be rubbed over either with a fine File, or with coarse Emery Paper, prior to their receiving the Browning Liquid, in order that its effect may be the greater.
In removing the Oxide from the surface of the Barrel, &'c., a Steel Scratch Brush will be found more effectual than the hard Hair Brush: the use of the Steel Scratch Brush is therefore to be adopted. This part of the operation must be done with great care, as upon it depends the proper Browning of the Barrel.
In moist Weather the operation of Browning must be performed in as dry a situation as possible, for humidity upon the oxide weakens the effect, which must be carefully guarded against.