IN WARFARE, an outgunned force that manoeuvres to shoot from behind
cover such as rocks or the rim of a ditch can often save itself from an
otherwise nearly certain rout. That, at least, was the opinion of Carl
von Clausewitz, a Prussian general whose treatise “On War” was the
handbook of many 19th-century military men. And modern ones, too. Almost
two centuries after Clausewitz committed his thoughts to print,
underdog forces such as the Afghan Taliban continue to make deadly use
of the art of concealment against technologically superior armies. But
not, perhaps, for much longer. For a collaboration between ATK, an
American firm, and Heckler & Koch, a German one, has come up with a
rifle that negates the advantage of cover which Clausewitz described, by
borrowing an idea from one of his contemporaries, Henry Shrapnel.
The XM25, as the new gun is known, weighs about 6kg (13lb) and fires a
25mm round. The trick is that instead of having to be aimed directly at
the target, this round need only be aimed at a place in proximity to
it. Once there, it explodes—just like Shrapnel's original artillery
shells—and the fragments kill the enemy. It knows when to explode
because of a timed fuse. In Shrapnel's shells this fuse was made of
gunpowder. In the XM25 it is a small computer inside the bullet that
monitors details of the projectile's flight.
A handful of XM25s are now being tested in Afghanistan by the
Americans. So far, they have been used on more than 200 occasions. Most
of these fights ended quickly, and in America's favour, according to
Lieutenant-Colonel Shawn Lucas, who is in charge of the weapon's
field-testing programme. Indeed, the programme has been so successful
that the army has ordered 36 more of the new rifles.
A new equaliser
Each rifle bullet is programmed, before it is fired, by a second
computer in the rifle itself. To determine the distance to the target,
the gunman shines a laser rangefinder attached to the rifle at whatever
is shielding the enemy. If that enemy is in a ditch, a nearby object—a
tree trunk behind or to the side of the ditch, perhaps—will do. Looking
through the rifle's telescopic sight, the gunman then estimates the
distance from this object to the target. He presses a button near the
trigger to add that value to (or subtract it from) the distance
determined by the rangefinder.
When the round is fired, the internal computer counts the number of
rotations it makes, to calculate the distance flown. The rifle's muzzle
velocity is 210 metres a second, which is the starting point for the
calculation. When the computer calculates that the round has flown the
requisite distance, it issues the instruction to detonate. The explosion
creates a burst of shrapnel that is lethal within a radius of several
metres (exact details are classified). And the whole process takes less
than five seconds.
Just how the turn-counting fuse works is an even more closely guarded
secret than the lethal radius—though judging by the number of failed
attempts to hack into computers that might be expected to hold
information about it, many people would dearly like to know. Certainly,
the trick is not easy. An alternative design developed in South Korea,
which clocks flight time rather than number of rotations, seems plagued
by problems. Last year South Korea's Agency of Defence Development
halted production of trial versions of the K-11, as this rifle is
called, and announced a redesign, following serious malfunctions.
The XM25, in contrast, appears to work well. It is accurate at ranges
of up to 500 metres. That is almost as far as America's main assault
rifle, the M-16, can shoot conventional bullets with accuracy. More
pertinently, it is nearly double the range of the AK-47, a rifle of
Soviet design that is used by many insurgent groups. And according to
Sergeant-Major Bernard McPherson, part of the XM25's development
programme in Virginia, it is receiving rave reviews from soldiers in the
field.
It is also inspiring imitation. Though several European countries are
planning to buy the XM25, some of them, including Germany, are working
on weapons that operate in the same way, but fire 40mm rounds. Such
bullets are easier (and less expensive) to make than 25mm rounds. But
starting with a smaller design increases the usefulness of the
technology. It is easier to enlarge components than to shrink them, so
the XM25 bullet design could, without too much trouble, be made to fit
ammunition intended for weapons with larger-bore barrels. ATK has
already begun modifying the technology to fit in the shells fired by
marine-corps artillery pieces, according to Jeff Janey, the firm's
vice-president of business development.
None of this is cheap. An XM25 with a thermal sight and a four-round
magazine is reckoned by informed observers of the field to cost about
$35,000. The bullets, which have to be made by hand at the moment, clock
in at several hundred dollars each. But the price of a bullet could
fall to as low as $25 when ATK switches to automated production. And
even at its current price, both gun and ammunition compare favourably
with alternative methods of dealing with dug-in gunmen.
The most reliable of these is an airstrike. But that is costly.
Grenade launchers, mortars and conventional artillery are cheaper, but
more likely than a single explosive bullet to cause collateral damage.
The upshot, then, is that though Clausewitz has had a good run, his
advice in this regard could soon become redundant. In coming years,
those who fight technologically advanced armies would be wise to note
that ducking for cover—one of the oldest ploys in combat—will no longer
offer the sanctuary it has in centuries past.
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