From: osan@cbnewsb.cb.att.com (Mr. X)
Newsgroups: rec.guns
Subject: Re: brass guns??
Date: 23 Jan 93 15:59:33 GMT
Organization: Twilight Zone

In article <1993Jan14.172501.10256@henson.cc.wwu.edu> n9020351@henson.cc.wwu.edu (James Douglas Del-Vecchio) writes:

#It got me thinking, if I were in the shoddy firearms business,
#and I wanted to make guns out of brass, say the same mixture
#that cases are made of: it seems like good stuff, would that
#put me in the same league as sleaze dealers like Davis and 
#Jennings?   

	If you used cartidge brass, you'd be sleaze, no question
	about it.  The formulations known loosely as "cartridge brass"
	are designed to be soft and malleable.  This is so that the
	cases can be drawn and machined with high quality and low cost.
	Drawing dies of the type used to draw cases undergo high pressures
	as it is.  A stronger brass would be harder on the dies, would 
	probably not draw well due to work hardening and would probably
	cost more to begin with.  The harder alloys don't all machine that 
	well unless annealed and you don't want your cases annealed at the
	head, precisely where the machining is done.
	
#I would want to think that I would be different from
#them somehow, of course.

	Sure Jim,  suuuuuuuuuuuuuuuuuure...

#What are the properties of brass vs standard zinc "capgun
#and 25acp alloy" potmetal?

Most bronzes (other name form brass, contrary to myth) will be stronger
that zinc and its alloys.  One passible exception is Zamak.  I've made a few
castings using this metal and it did not impress me AT ALL.  Pretty cheap
stuff.  I was surprised that it was strong enough to use in a gun.  I also
noticed that I have not seen anything bigger than a .25 or .32 using this
material.  Are there any, say, 9mm or 380 ACPs out there that are made of this?
The idea gives me the willies, but who knows, maybe it is safe.

#
#I assume there is a strength difference, and hopefully there
#is a cost advantage over steel.    This would be cast and low
#volume.

	Brass is generally sognificantly more expensive than steel, but
	of course there are exceptions.  I am not so familiar with barrel
	materials, but I suppose they might more expensive than your typical
	bulk mild steel, though I would not know how much of the extra
	cost would be in the metal itesl as opposed to the processing costs.

	At any rate, the types of brass that I think you  would probably
	want to use would be fairly expensive.  Phosphor bronze is very
	strong stuff, casts beautiifully and is work hardenable, if not
	heat treatable (I could look this up).  However, it MIGHT be too
	brittle.  I don't believe it will get over an Rc hardness of 35 or 40,
	but at peak hardness the interstitial bonds in the crystalline
	structure of the metal are full of tensions and I am not sure if this
	would not cause a toggle type of failure in a barrel rather than
	a bulge.

	Another material that would probably be an EXCELLENT barrel choice
	would bt Berylco Nickel-440(tm).  A 2% Beryllium alloy of nickel.
	This stuff is STUPENDOUSLY straong and can be solution treated
	(basically a T6 treatment == solution tratment and precipitation
	hardening) , work hardened and artificailly aged (basically a 
	stress relieving procedure) to an Rc hardness of ~52-55 which is
	harder that most kitchen knives.  It would be stain free, a good
	heat sink and stable.  Main draweback is cost which runs around
	$25-50 per POUND (depending on the Beryllium market which is a bit
	weird, as I understand).  It is also NOT a free machining alloy,
	i.e. you   would probably need some fairly exotic tooling in order
	to get good finishes, which means either diamond tools or thin
	film diamond coated carbides or Cubic Boron Nitride (CBN).  In either
	case this gets expensive.  Also you might run into trouble with the
	finish grinding processes since nickel is nonferrous, which means
	it might tend to glaze wheels.  The beryllium may mitigate this, I
	am not sure.  Metals like Aluminum and Titanium and brass & copper
	are nearly impossible to grind as the wheels load up almost instantly
	in most cases.  Titianium is really lousy to work with, but I digress.

	I have not machined N440, but I have machined its beautiful sister
	Be copper.  What a BITCH!!  BeCu has the most God awful habit of tearing
	at the surface and wearing tools out (high speed steel, i.e.)  Almost
	impossible to get a good finish.  My foster father, the finest most
	incredible machinist (instrument maker) ever to walk the earth knew
	how to machine this stuff perfectly.  He told ne it is all in the
	they way the tool is ground and your speeds and feeds.  But...
	

	So, Yes I'm sure you could make brass guns, but I am not sure they 
	would be any cheaper.  They sure look nice though!

	-Andy V.