From: Gale McMillan <" gale"@mcmfamily.com>
Newsgroups: rec.guns
Subject: Re: Please Tell Me About Rifle Barrels
Date: 7 Mar 1997 16:33:49 -0500

Tony Vanchieri wrote:

# I am having a hard time understanding the difference between
# different barrel making techniques.  I have checked the rec.gun
# archives and could not find an answer, so I hope to appeal to
# the expertise here for help!
# 
# What is a broach and a button-cut?  What are the differences,
# and which is considered "best?"
# 
# Any help is greatly appreciated!


There are three basic types of barrels.  The oldest in use today is the
cut rifle barrel.  It is made by pulling a cutter through the barrel
scraping metal away from the bore in a spiral.  The uniformity of
dimension depends on the even homogenization of the alloys and the
uniformity of the hardness of the steel.  This method does not make as
dimensionally uniform barrels as the other methods.  Buttoned barrels
are made by pulling a carbide button which is several thousands of an
inch larger than the diameter of the bore.  This button is shaped like a
football with groves cut into it on a helix of the twist desired.  The
button expands the bore out to grove diameter but leaves the area under
the groves at bore diameter.  This forms the rifling.  This type of
rifle barrel has held most of the national and world records over the
past 40 years.  Although most high power shooters will argue, you can't
change the records.  I saw button tooling in the barrel shop at Parker
Hale that dated back to the mid 30s, but it didn't get popular here until
after the second war.  The third method is hammer forging that came
along when the large manufacturers decided to sacrifice quality for
speed and cost.  This method pounds a piece of steel that has a hole in
it over a mandrel that has the rifling cut into it.  It swages the
barrel down to the desired measurement in a very short time.  There is 2
types of hammer machines, one starts with the barrel blank at finished
length and hammers straight down as the blank is pulled under the
hammer.  The other type starts with a billet 8 or 10 inches in length
and kneads the steel over the mandrel in the final shape.  This method
sometimes forges the chamber at the same time.  When you hammer a barrel
over a mandrel it has a certain amount of spring back.  Otherwise you
wouldn't be able to get the mandrel out.  This also causes it to be
dimensionally inaccurate.Of all the methods used today Hammer forging
makes barrels faster and cheaper but of poorer quality.  There are
barrels being made by electro discharge (EDM) and a few pistol barrels
are made this way but for the present time it isn't used enough to
consider it a method.

I hope this helps you understand the different methods.

Gale McMillan

From: Rock McMillan <mcbros@indirect.com>
Newsgroups: rec.guns
Subject: Re: Making your own rifle barrel
Date: 7 Dec 1995 10:33:47 -0500
Organization: McBros RIfles

Filipo64 wrote:

# Does anybody have a source of info on making your own barrel? I've been
# shopping around for a new custom benchrest rifle - and prices are really
# high. I have a friend who is an excellent machinist, and he got interested
# after looking at my .300 Arnold.

If your goal is to save money you are wasting your time, there is 
absolutely no way you can make your own barrel as cheap as you can buy 
one.

It's not impossible to make your own barrels, my uncle made the first 
"McMillan" barrels on his small engine lathe and a homemade buttoning 
machine in his storeroom.  But you have to understand that he was an 
exceptional person, a real one in a million. A little sideline here, 
most people don't know that Millard McMillan made the first "McMillan" 
barrels and latter turned the technology over to my uncle Pat who made 
the "McMillan" barrel famous.  The world record .009 inch 5 shot 100 
yard group was shot by Millard with one of his own barrels.

It takes a gun drill that can turn about 3600 rpm and pump approximately 
500-700 psi cutting oil pressure.  It also takes a gun drill cutting 
tool costing around $200.  After you drill you need to ream with another 
$200 tool on a different machine.  Next you need to figure out what 
rifling you want, cut or buttoned.  If you choose cut rifling you need a 
rifling machine, probably will have to build one.  You also need a 
rifling cutting head and cutting tool.  If you choose buttoned you need 
to build a buttoning machine and have carbide buttons ground.  After 
rifling you need to conture on a tracing lathe or CNC lathe and then you 
need your own stress relief oven.  To really get the tools the way you 
want them you ought to make your own on a $10,000 to $15,000 tool and 
cutter grinder and spend months or years prefecting them.

With all this in place you will need a truck load of ordinance grade 
steel (2000 to 10,000 lbs), can only be ordered in mill lots and takes 
20-30 weeks to get.

I grew up in a family of barrel makers and I saw how many barrels they 
hauled to the dump before they got the hang of it.  My father and uncles 
all ended up with not much hair on top, probably from all they pulled 
out trying to figure out how to make barrels.

If after reading this you still want to try it just for the fun of it 
let me know and I'll try to help.

Rock McMillan
McBros Rifles