my reply is kinda long.
I also copied this from
[url] http://www.cascity.com/forumhall/index.php/topic,11991.0.html[/url]
Nolan Sackett wrote this for
[url] cascity.com[/url] website.
Nolan Sackett is the master leathercrafter for wild rose trading company. He specialezes in old time leather working methods.
If you need more information on this subject send nolan sackett a email with questions. he is very happy to help out leathercrafters. just look up wild rose trading company for his email address. enough of my rambling here is Nolan's instructions. i'm sure you can adapt them to whatever shells you have on hand.
hope this is what your looking for.
Rember this entire segment is a quote from Nolan Sackett's post on another forum.
Here's some instructions for some of the old time dyes I'm working with these days:
1) Black: VINEGAR BLACK (aka Vinegaroon - these are original old formulas)
For giving color to the grain of leather there is no blacking that will at all compare with the well known vinegar black. This may be made in various ways. The simplest, and, without doubt, the best, is to procure shavings from an iron turner and cover them with pure cider vinegar; heat up and set aside for a week or two, then heat again and set in a cool place for two weeks; pour off the vinegar, allow it to stand for a few days, and draw off and cork up in bottles. This will keep for a long time, and, while producing a deep black on leather, will not stain the hands.
Another method is to cover iron scraps with sour beer, and allow them to stand for a month or more; then strain off the beer and bottle as before.
A third method is to boil sulphate of iron in vinegar; mix some brewer's yeast with beer and allow it to stand for twenty four hours, then skim off the yeast and add the vinegar.
Instead of iron shavings you can use steel wool. To use the steel wool burn off the oil first - I dip it in acetone and use a propane/blow torch and light it off in an old pan with a lid, just in case you need to put the flame out. Take all precautions and it will work fine. The only problem with steel wool is it often has copper and other metals in the "mix" which can sometimes add a greenish tint.
After the "dye" (actually it's a reagent) dries I then neutralize with a slurry of baking soda and room temp water, about a 1/2 cup baking soda to a quart of water. Then I let the leather dry until just damp and apply a light coat or two of oil (I generally use olive oil, Lexol, Conditioner, or Lexol non-greasy Neats Foot). When the "dye" first dries it may look bluish or grayish at first and sometimes a second coat is needed, but normally the neutralizing and oil will turn it black.
2) Brown: I use black walnut hulls (If they are not available locally - the fresh green hulls are best - you can buy them dried on line from various vendors - to find a vendor search for walnut dye, etc.) Put a pound or so of the crushed hulls in an old stocking and place in a pan of distilled water so that the water covers the walnut hulls about an inch. Cover it and simmer at a low boil for several hours and then let cool overnight - keep an eye on the water level. The next day boil again and let cool overnight. Again watch that the water level does not get too low, but you do want it to get fairly thick. Once it's cool drain off the liquid be sure to squeeze all of the liquid out of the bundled walnut hulls. Save the walnut hulls - hang them up to dry and you can use them a couple of times more. The liquid will go bad so either keep it frozen or add 3/4 of a cup of rubbing alcohol to a quart of the dye. This is the dye I used on the Slim Jim in the DVD. It will come out anywhere from a light brown/gray to a dark grayish brown before oiling (I use light olive oil a lot for oiling and then set it in the sun to darken) - the color will depend on the leather - every piece is different, how long you let it soak, and how strong the dye is.
I always do a test on a scrap of every new hide, I use only American tanned hides - mostly from Wickett & Craig. You can also mix the two dyes, which gave me a rusty/black on the pieces shown below. I used a 60/40 mix of walnut to vinegaroon on the belt and a 75/25 on the holster: