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December 2, 2003, 5:49 pm
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Leo Kelly , Auckland
Firing handguns into the air is commonplace
in some parts of the world and causes injuries with a disproportionate number
of fatalities. For a typical modern 7.62 millimetre calibre bullet fired
vertically from a rifle, the bullet will have a velocity of about 840 metres
per second as it leaves the muzzle and will reach a height of about 2400
metres in some 17 seconds. It will then take another 40 seconds or so to
return to the ground, usually at a relatively low speed which approximates
to the terminal velocity. This part of the bullet's trajectory will normally
be flown base first since the bullet is actually more stable in rearward
than in forward flight.
Even with a truly vertical launch, the bullet
can move some distance sideways. It will spend about 8 seconds at between
2300 and 2400 metres and at a vertical velocity of less than 40 metres per
second. In this time it is particularly susceptible to lateral movement by
the wind. It will return to the ground at a speed of some 70 metres per second.
This sounds quite low but, because of the predominance of cranial injuries,
the proportion of deaths and serious injury as a proportion of the number
of gunshot wounds is surprisingly high. It is typically some five times more
than is observed in normal firing.
As might be expected, measurements
are rather difficult and the above values come from a computer model of the
Sam Ellis And Gerry Moss , Royal Military College of Science
Different bullet types behave in different ways.
A .22LR bullet reaches a maximum altitude of 1179 metres and a terminal velocity
of either 60 metres per second or 43 metres per second depending upon whether
the bullet falls base first or tumbles. A .44 magnum bullet will reach an
altitude of 1377 metres and a terminal velocity of 76 metres per second falling
base first. A .30-06 bullet will reach an altitude of 3080 metres with a
terminal velocity of 99 metres per second. The total flight time for the
.22LR is between 30 and 36 seconds, while for the .30-06, it is about 58
seconds. The velocities of the bullets as they leave the rifle muzzle are
much higher than their falling velocities. A .22LR has a muzzle velocity
of 383 metres per second and the .30-06 has a muzzle velocity of 823 metres
According to tests undertaken by Browning at the beginning
of the century and recently by L .C. Haag, the bullet velocity required for
skin penetration is between 45 and 60 metres per second which is within the
velocity range of falling bullets. Of course, skin penetration is not required
in order to cause serious or fatal injury and any responsible person will
never fire bullets into the air in this manner.
The questioner may like
to read "Falling bullets: terminal velocities and penetration studies", by
L. C. Haag, Wound Ballistics Conference, April 1994, Sacramento, California.
David Maddison , Melbourne Australia
John W. Hicks in his book
The Theory of the Rifle and Rifle Shooting describes experiments made in
1909 by a Major Hardcastle who fired .303 rifle rounds vertically into the
air on the River Stour at Manningtree. His boatman, probably a theorist unaware
of the winds aloft, insisted on wearing a copy of Kelly's Directory on his
head. However, no bullets landed within 100 yards, some up to a quarter of
a mile away and others were lost altogether.
Julian S. Hatcher records
a similar experiment in Florida immediately after the First World War. A
0.30 calibre machine gun was set up on a 10 feet square stage in a sea inlet
where the water was very calm so that the returning bullets could be seen
to splash down. A sheet of armour above the stage protected the experimenters.
The gun was then adjusted to centre the groups of returning bullets onto
Of over 500 bullets fired into the air, only 4 hit the stage
at the end of their return journey. The bullets fired in each burst fell
in groups of about 25 yards across.
The bullets rose to approximately
9000 feet before falling back. With a total flight time of about a minute,
the wind has a noticeable effect on the return point.
Dick Fillery ,
Content-Type: text/plain; charset=us-ascii; format=flowed
Does anyone have some of these to sell.
The US webs sites that shows them says there are 7 week lead times !!
I am in Colorado.
Re: I once......
I thought it was one of the troll posts with Followup-To set for
news.admin.net-abuse.email that've splattered across Usenet recently.
Then I noticed the lack of Followup, which puzzled me. :^)
Google on "space bullets" for more of the "must come down" side of things.
An unfortunately "embedded" application.
An unfortunately "embedded" application.
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