Muriatic Acid

[Duane Harshaw]

  Has anyone used this to brown steel, we can't get LMF brown up here.D

[Mark Elliott]

I have only used Muriatic Acid to clean and strip zinc.   I think that might be a bit too aggressive for browning.  Vinegar rusts clean steel pretty good.   A damp box might be a good investment.

[heinz]

Muriatic is HCl, hydrochloric acid.  Not good for browning, tends to be a rust remover.  Ammonium chloride, also know as Sal Ammoniac, is an old time tinning flux.  In a 2% to 5% solution, it will brown niclely if you are a bit patient.  The stronger, the faster but will also pit a bit when strong.   

[Scota4570]

Hydrochloric acid is not a good choice.  Others will chime in. 

I concentrated my efforts on quick browns. I got best results in my area with birchwood Casey Pumb brown.  IF you look up the SDS for the item you want you can get an approximation of what is in it.  IT has nitric acid which is nasty stuff.  You could try the same SDS strategy for whatever you are interested in. 

https://www.birchwoodcasey.com/content/datasheets/14130%252c-14145-Plum-Brown-Liquid-Barrel-Finish.pdf

The old Birchwood Casey formula had mercuric chloride.  Even nastier stuff.  Avoid it at all costs.

I did find that I could make a decent quick brown with stannous chloride and and oxidizer, dissolved in distilled water.   Ammonium nitrate, worked well as did potassium nitrate.  Potassium nitrate is sold as stump remover.  For easily found ingredients I might try table salt and stump remover in water.  Swab it on a hot piece of steel.  You will probably get rust. 

If at all possible please buy professionally prepared solutions. 

That said, Aniger wrote a whole book on the blueing and browning of firearms.  It has lots of formulas.  As I wrote before avoid anything with mercuric chloride.  IT is a potent neurotoxin. 

[Not English]

Duane, I use it for exactly the opposite. I've browned a few TC barrels for friends. Muriatic/Hydrochloric acid leavers a very nice gray surface That bis ready for browning with nothing more than a good rinse. I'll also second the Angier book. It's dry reading but loaded with info.

[Eric Krewson]

I grabbed the wrong bottle one time without noticing and used aqufortis on a barrel, it browned it like a champ.

[Scota4570]

Ferric nitrate produces rust as does ferric chloride.  That is a good option.  In warm humid areas making rust is easy.  In cold dry areas, like mine, not so easy.  OP was in Alberta.  IT might be tough for him.  I've used cold blue on several guns lately.  If I apply it with   scotchbrite until it bites evenly the results are very good. 

[Mad Monk]

I grabbed the wrong bottle one time without noticing and used aqufortis on a barrel, it browned it like a champ.

According to one browning book I looked at the use of nitric acid to brown iron was fairly common.  When I made ferric nitrate solution for staining using large pieces of 100 year old iron they browned nicely once removed from the nitrate acid conversion bath.

In a discussion with Chuck Dixon one year he commented about the browning of the original barrels starting at the edge of the wood against the barrel. We wondered if the old gunsmiths browned some barrels when they were mounted in the stock when the stock was stained.  The originals show no browning or rust where the barrel is covered by the wood.  So I tried it with one rifle build and it worked out well.  The stock was stained and the barrel was browned.  And the ferric nitrate solution did a very nice job of browning the top half of the barrel not covered by the wood.

[DGB]

This reply is not specifically about acid ,but might be helpful for your browning.
For a sweatbox, I use a hard plastic gun case.
Just take out the foam padding . Put your coated barrel in there with some wet cloth and close the lid. Has been working fast for me.
No extra building projects are wasted space needed for barrel browning,
Regards,
Dave

[Scota4570]

This guy is clever.  The video explains how to rust blue with virtually no specialized tools.

[B.Habermehl]

You can brown a barrel with salt and calcium chloride. Calcium chloride is the same thing as sidewalk deicer or pickling crisper from the grocery store. Both of these are non toxic in sensible quantities. Except in California then your on your own GBG. 

[eggwelder]

I have used muratic acid-(pool acid) to remove rust of small antique car parts.
Rinsed them off with water, and rusting the next day. This was when i lived in Edmonton, Alberta, which, for the most part, is dryer than a popcorn @$#%.
I have a piece of barrel, and some muratic acid- i think i will test this.

[Not English]

Madmonk, that's an interesting bit of info! I've seen this before and was always of the opinion that the barrels were originally white, and had rusted from the atmosphere over 200 yrs. These were high quality rifles and a white barrel would have been more than appropriate. It really bears some thinking about and more investigation. Thanks for posting.

Dave

[Mad Monk]

Madmonk, that's an interesting bit of info! I've seen this before and was always of the opinion that the barrels were originally white, and had rusted from the atmosphere over 200 yrs. These were high quality rifles and a white barrel would have been more than appropriate. It really bears some thinking about and more investigation. Thanks for posting.

Dave

You see in old gunsmith records that the gunsmith would sell rifles with barrels brown or in the "white".  To brown only that area of the barrel not covered by wood would be silly and not match what we saw in some originals where the browning stopped exactly at the wood.  I should also mention that with the ferric nitrate as a browning solution there are not all of the after rusting problems seen with the various chloride browning compositions.  In Dixon's big collection we saw barrels where the browning as rather blotchy and then some where the browning was uniform in every respect for most of it's length.  I had a book written by I think Anger on browning and blueing and he stated that the ferric nitrate was once using as a browning solution.  I did two rifles like that and it went quick with the barrel in the stock when staining the wood and then browning the barrel in what was one quick operation.

[gusd]

As heinz does, I use sal ammoniac. Comes in cake form, like a bar of soap.
I cut into cubes ,mix with water. Can be very aggressive, be watchful of progress.
Buy from suppliers of stained glass supplies.
gus

[deepcreekdale]

I have an old book from the 1940's-50's that said they used urine to brown barrels. I have  no idea how they came up with that idea and what their source was. I guess it might work but I think I will let someone else try it first.

[Mad Monk]

I have an old book from the 1940's-50's that said they used urine to brown barrels. I have  no idea how they came up with that idea and what their source was. I guess it might work but I think I will let someone else try it first.

That is true when you back about 200 to 300 years ago.  Mice got into a buddy's gun cabinet.  Mice urine did real nasty things to his stored guns.  Then in my younger days I spent a bunch of hours in the back of the manure wagon at the wife's uncle's farm.  The metal belt that feed the manure into the thrown bar was always broken becuase the urine in the manure really corroded the bars and bolts.  So I had to heave the stuff into the rotating spreader with a pitchfork.

With that old thing about the urine.  You may see it described as "stale urine".  The mammal urine is high in salt.  Chlorides.  Then you had bacteria converting protein in the urine over to ammonia.  The combination of the chlorides and ammonia made the urine highly corrosive.  You will also see ammonium chloride being used as a browning solution.  Also seen as salamoniac.  I bought it in a dry crystal form and mixed it with water as needed.  A 2% to 5% solution on the barrel after a good solvent cleaning.  About 4 hours standing in a damp corner in the back of the basement.  Lots of rust and fast.

The thing about ammonia and chlorine or chlorides is why we no longer see metal parts inside our home toilets.  Once the municipal water systems started adding ammonia as a buffer in the treated water that combined with the chlorine was death to any brass or iron parts in the toilet innards.  Then in this town they add fluorine to prevent tooth decay in children.  Then what you end up with is water containing the three most corrosive chemicals you can find in nature.  In the chemical plant I worked in we had a 3/8" steel tank that held recovered monomer that contained this fluorine and chloride combination.  Generally a steel tank lasted about 3 years before the liquid ate through the 3/8" steel plate.