From: "David Johnson", [EMAIL PROTECTED]
F.W.Mann, in "The Bullets Flight", published in 1909,
looked reported on bullet melting while investigating
the instability of bullets in flight. In his experiments
he place paper screens all down a 100-yard range to
record the trajectory of the bullet. This is his account
of one of the experiments:-
Jacketed Bullets throw Melted Lead.
Test 173. - September 24, with Springfield barrel,
.30-40 Government Krag, 220-grain U. M. C., soft-nose
bullet, to test the oscillations of an unbalanced bullet
from a government rifle, Springfield barrel; and Plate
(38), produced from this test, is quite interesting.
Number 3 bullet was drilled close to its base .1 inch
in diameter, removing 2.4 grains metal, and Nos. 1 and 2
with larger drill, removing 4 grains metal.
These mutilated bullets were entered by the shell as
nearly as possible in same position, but what that
position would be when emerging at muzzle was not known
except as could be told by the tip.
The bullets oscillated regularly in the same period as
the old .32-caliber black powder ones, with no tip at 11
feet. The maximum tip of No.1 at 6 feet was 11 degrees
and was deflected .23 inch at 12-foot cross.
The interesting feature of this test was the pouring of
melted lead out of the drill holes, probably due to the
excessive heating of the metal jackets by friction; this
heat, passing through the jacket, melted more or less of
the lead core before the first bullet reached the 8-foot
screen, the 2d one the 2-foot, and 3d the 5-foot screen.
The melted lead poured out of the drill holes of all
three bullets to and past the 16-foot screen.
The three shots thus illustrated by markings of melted
lead were made, commencing with a clean rifle, the bore
being in very good shape and cleaned easily, though it
had been slightly corroded before coming into our
possession.
After such a marked heating of bullets several other
tests were made on succeeding days with different forms
and makes of bullets, and with vents in jackets at various
distances from their bases, but in no day or with any
condition did they throw so much melted lead as shown on
Plate (38); that the markings on the screens were made by
lead and tin, we determined by chemical analysis.
He also had a few comments to make about 'bullets jumping
the rifling', which has also been mentioned in recent
postings:-
In addition to the above tests, a well-known fact may be
recalled, one which has been in print several times, and
vouched for to me by Mr. Pope. If a regular .32-caliber
smooth bore be placed in a rifling machine, and the
rifling head be exchanged for a lead plug containing coarse
emery, the slight scratches made are sufficient to properly
rotate the normal projectile for this bore, and the rifle
for a few shots will do fair work.
Still further, we can look back over the period from 1900
to 1907, during which hundreds of different styles of
bullets were recovered in snow or oiled sawdust, without
mutilation. All were examined and usually with a glass,
yet in no one case was there a suspicion of the grooves
being stripped or even widened. One .38-caliber Babbitt
metal bullet, bore diameter and 55-grain powder charge,
upset so slightly that only the faintest trace of the land
was left upon its surface, and yet, when taken from the
snow, the land mark seemed normal as to width. This bullet
had 110 base band which could engage the grooves. Two
grains of lead were gas-cut from this bullet, and yet, as
far as could be detected, it followed the grooves well.
Anyone with an interest in ballistics should try to get hold
of a copy of Mann's book. The experiments he did answered
many of the questions that are still being asked and argued
over!
Dave Johnson
Cybershooters website: http://www.cybershooters.org
List admin: [EMAIL PROTECTED]
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