Subject: Re: Browning vs. Bluing

From: [email-masked] (Michael Edelman)
Date: 4 Dec 1996 20:32:46 GMT

Alan K. Gideon ([email-masked]) wrote:
: I understand that a process called "browning" was used as a surface
: protection for rifle barrels in the 19th century, like bluing is now. 
: I've seen the result, but I'm not too sure about trying it just because
: it is advertised as "historically accurate."  What time frame was it
: used in?  Why is it no longer used; simply because bluing produces a
: prettier finish?  Is there some hidden failure mode, like crevice
: corrosion, to worry about?  Exploding gun barrels are not a fun thing to
: think about.

Traditional rust browning is done by repeatedly allowing a very thin 
layer of rust to form in a humid cabinet and then carding it, i.e.,
burnishing off the loose rust. Today's it's done with steel wool.

Rust bluing adds another step: Boiling the part in water. This converts the 
red iron oxide to black iron oxide.

I think the black oxide is a tougher coating, but I have a rust-browned
pistol I did 20 years ago that hasn't changed or developed any pitting.

I don't know when bluing too over. I have an English shotgun from 1820 
that was browned. I think the conversion was a gradual process over
many years.

--mike

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From: "Alan K. Gideon" <[email-masked]>
Date: Tue, 03 Dec 1996 16:03:37 -0500

I understand that a process called "browning" was used as a surface
protection for rifle barrels in the 19th century, like bluing is now. 
I've seen the result, but I'm not too sure about trying it just because
it is advertised as "historically accurate."  What time frame was it
used in?  Why is it no longer used; simply because bluing produces a
prettier finish?  Is there some hidden failure mode, like crevice
corrosion, to worry about?  Exploding gun barrels are not a fun thing to
think about.

Thanks.

-- 
Alan K. Gideon, P.E. | Naval Architect & Marine Engineer
                     | [email-masked]

"War is an ugly thing, but not the ugliest.  The ugliest is that man 
who thinks nothing is worth fighting or dying for, and lets men 
better and braver than himself protect him."   --   John Stuart Mill

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From: [email-masked] (E.M.Bortmes)
Date: 6 Dec 1996 17:15:52 GMT

In article <[email-masked]>, [email-masked] 
says...
>that was browned. I think the conversion was a gradual process over
Actually the modern black finishes are produced by oxidizing the iron 
at very specific conditions (using a powerful oxidizing agent) to 
produce a coating that is Fe3O4  The older coating produced an iron 
oxide that was Fe2O3.  I personally like the black better, IMHO it is 
also more wear resistant. As you know, if you heat a piece of clean 
iron you can see many oxide colors ranging from straw to black.

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From: [email-masked] (Peter Brooks)
Date: 6 Dec 1996 19:23:57 GMT

I built one muzzle loading pistol and browned it; the other pistol and
rifle were blued.  I wasn't thrilled with the mercury compound needed
for browning, but for the limited use I had with the cap-lock, it
served well.  Got a nice, plum brown, too.

I like the looks of browning, but using a cold blue was a *lot* easier.
(Brownell's Oxpho-blue)

Pete Brooks

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From: Rick Cook <[email-masked]>
Date: 5 Dec 1996 05:02:17 GMT

>corrosion, to worry about?  Exploding gun barrels are not a fun thing to
Browning simply referred to a rust finish. Properly done it was hard,
durable and not harmful to the gun. Essentially it involved putting the
part in a humid enviornment with a lot of salt, letting it develop a coat
of rust and then brushing off all but the most tightly attached rust.

I've used the process, although not on guns. It works well and produces and
even finish that protects the underlying metal. However I suspect bluing
(which is a more complex process) actually does a better job. Certainly you
can have a more highly polished blue finish.

--RC