DU

[Lester.Slaback@nist.gov]

As a minor added point DU is attractive not only because
of its density but also because of its (initial) cheapness
and pyrophoric property.  The later certainly aids in penetrating  thick
armour.

I qualify 'cheapness' because post usage cleanup and response to people
worries may offset those cost savings (compared to using tungsten),
although I suspect that this is not an issue for  the guy using the
weapon.
-- 
the above are the personal musing of the author,
and do not represent any past, current, or future
position of NIST, the U.S. Government, or anyone else
who might think that they are in a position of authority.
NBSR Health Physics
NIST
Gaithersburg, MD 20899
301 975-5810
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Lester.Slaback@nist.gov
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