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From: stiatl!john@gatech.edu (John DeArmond)
Newsgroups: sci.military
Subject: Re: Kissinger on Micronukes
Message-ID: <5543@cbnews.ATT.COM>
Date: 11 Apr 89 05:21:28 GMT
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From: stiatl!john@gatech.edu (John DeArmond)

In article <5514@cbnews.ATT.COM> vrdxhq!vrdxhq.verdix.com!bobs@uunet.UU.NET (bobs) writes:
>
>
>From: vrdxhq!vrdxhq.verdix.com!bobs@uunet.UU.NET (bobs)
>
>> 
>> From: sun!portal!cup.portal.com!mmm
>> As I recall, Henry Kissinger in one of his books used as an example of
>> how technology can suddenly change the political environment, a speculation
>> of the effect of the development of a nuclear bullet.  In particular, 
>> sponge californium.  Californium has a critical mass of a few grams, so
>> in principle a bullet might be developed which would produce a nuclear
>> explosion on impact.
>
Californium is not a candidate for this.  Exactly because of it's 
spontaneous fission which results in a neutron field at all times and
because of its cost (several thousand dollars a MICROGRAM), it would
not work in practice.

Consider that the critical mass of plutonium is only a couple of Kg's,
a mass of perhaps the size of a baseball, nuclear rounds for light
cannon are already practical.  Also consider that such techniques as
neutron triggers can substantially reduce the mass of fissional material
and consider that an explosion from a nuclear bullet need not be very 
effecient, conventional technology could be used to make much smaller
rounds than one would think.

>I remember reding that the depleted uranium rounds of the GAU-8
>( 30 mm gun on A-10s) deforms enough on penetration that it becomes
>a critical mass and puts out a burst of radiation. I believe gamma
>was mentioned but it has been a while. The emphasis of the report was
>
>[mod.note:  I'll head off a number of probably replies by stating, 
>"I don't buy it."  I understand that DU (depleted uraniaum) has a
>significant pyrophoric effect (i.e., it burns), but I sincerely doubt
>that it can be brought to any degree of fusion by this impact,
>tremendous though it may be.
>


Bill is indeed correct.  U-238 (depleted uranium) has no critical mass.
It will not sustain a nuclear reaction without outside nuclear influence
such as a fast neutron flux.  Metallic U is pyrophoric and makes a 
pretty good mess if it penetrates the armor.  The tiny amount of radiation
emitted by U-238 is a non-existent hazard when compared to flying globs
of high velocity, very heavy, white hot, and burning U metal.  Not to
mention the spalled armor shards.  The nuclear aspect of depleted U 
projectiles is strictly incidental.

-- 
John De Armond, WD4OQC                     | Manual? ... What manual ?!? 
Sales Technologies, Inc.    Atlanta, GA    | This is Unix, My son, You 
...!gatech!stiatl!john                     | just GOTTA Know!!!