HB-9 updated text (PDF) - Corbin Bullet Swaging

the copper is drawn down and shaped into a jacket, it will harden slightly
but the surface may not be burnished enough to get rid of the porous
layer. I think this layer is what comes off in the bores.
Nearly all metals will leave something of themselves in the bore, but
we are talking about fouling bad enough so that it is a problem, an exceptional
amount of fouling. And with properly drawn and polished bullets, I
have not seen any significant problem. With the highly finished copper
strip that we use for making drawn bullet jackets, there is no problem
worth consideration.
Some of the rumor probably comes from the fact that people who do
this sort of experimental work with bullets are more curious and inspect
their guns more carefully than people who just buy factory bullets, and
they notice even a small amount of fouling sooner. Some of it comes
from the loose, porous finish that experimenters may get on their torchannealed
copper tubing jackets. So, use annealed copper instead of annealing
it with a torch, or polish the jackets so that the outer surface is
removed down to the hard underlying metal. Don’t worry about it unless
you actually experience a problem, which you probably won’t.
The Myth of Mysterious Rites of Swaging
I’ve heard all these tales about how you have to let the bullets “rest”
overnight before you shoot them, or how you have to swage cores and
then put them in a jar and give them a day to “normalize” (whatever that
means) before putting them into the jackets. Hardened lead alloys often
change hardness over a period of time after having been subjected to
stress, such as swaging, but if you are interested in accuracy you probably
use pure lead wire (which has no such time-related hardness change).
Most of this is purely in the mind of the person who believes it, and
came about either because someone else said it, or because the person
happened to shoot a great group one day after doing something of the
kind and from that day forth will always give the ritual credit. I wonder if
a hunter who dropped his rifle and had it go off and by sheer luck shot a
deer with that stray bullet would henceforth go into the woods and toss
his loaded rifle on a rock?
I suppose we all know people who got lucky one time with totally
inappropriate equipment or techniques, and without any further testing
just assumed that the thing they did incorrectly was responsible for the
good fortune of that day. Likewise, bad results are sometimes blamed on
coincidental precursors. A statistic says that 80% of all people killed in
car wrecks ate carrots during the previous twelve months. So, does this
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