Subject: Re: RDX, is this correct...?
From: glhurst@onr.com (Gerald L. Hurst) 
Date: Apr 13 1996
Newsgroups: rec.pyrotechnics,alt.pyrotechnics,alt.engr.explosives

In article <4kmh5c$leu@lscruz.scf.lmsc.lockheed.com>,
leep@mailhub.scf.lmsc.lockheed.com (leep) says:

>50/50 tnt/rdx is known as pentolite and may still be used
>in grenades. The tnt is used to add "throwing power" of the 
>metal fragments as rdx doesn`t have as much throwing power. Bruce

The addition of TNT REDUCES the "throwing power," i.e. fragment 
velocity because RDX is more brisant and has more energy than TNT.
TNT is used as a meltable, energetic flux for otherwise uncastable
explosives such as PETN, RDX, tetryl, AN, HMX and the like. Except
in the case of AN, the addition of TNT generally drops performance
on a pound for pound basis. With AN, of course, there is an oxygen 
balance synergism which gives an overall improvement in energy if
not brisance (compared to TNT) to the mixture.

Jerry (Ico) 

From: glhurst@onr.com (Gerald L. Hurst)
Newsgroups: alt.engr.explosives
Subject: Re: Mixture balances
Date: 18 Feb 1997 18:53:27 GMT

In article <magd0005-1802971106060001@pub-11-c-176.dialup.umn.edu>,
magd0005@tc.umn.edu (Karl A Magdsick) says:

>  It is my understanding that most explosive mixtures achieve maximum
>power at a neutral oxygen balance.  However, is there a rule of thumb to
>follow in order to estimate the optimum mixture of two or more explosives
>with a negative oxygen balace.  In this case, getting the oxygen balace
>closest to zero wouldmean having a 100% mixture of the explosive whith on
>oxygen balance closest to zero.
>  Another way of stating my question is this: is there way to calculate
>the optimum (70/30) mixture for octol without experimentation?

The TNT in octol merely serves as a flux or vehicle to make the 
explosive castable. There is little point in striving for oxygen 
balance.  The best procedure is to simply use as little TNT as is
required for castability.  If oxygen balance is important for 
some special reason, throw in some inorganic nitrate or the like.

The idea of achieving maximum "power" depends on what you mean by
"power."  Generally, overall energy output is improved by balancing
fuel and oxidizer but this gain may be at the expense of brisance
or loading density.  For example, TNT and AN can be blended to form
much more nearly oxygen-balanced amatol. This product easily 
outperforms straight TNT in the balistic mortar test (heave) but is 
noticeably inferior in fragmentation tests.

Jerry (Ico) 

Subject: Re: Cutting TrinitroToluene (TNT)
From: glhurst@onr.com (Gerald L. Hurst)
Date: Mar 12 1997
Newsgroups: alt.engr.explosives,rec.pyrotechnics

In article <Pine.OSF.3.91.970312122834.22491A-100000@alfa.ist.utl.pt>,
The Alchemist <l40619@alfa.ist.utl.pt> says:

> Hi Explosives Experts ...
>
>In the lab where I live(!) at university ... I've seen a bottle with 
>three or four big bars (0.5 pounds) of TNT imersed in water (I think it's 
>water). What's the way to cut a little piece of those bars??
>Should them be cut with a metal blade ?
>How dangerous is it ?

Are you sure that it is really TNT?  I can think of no earthly
reason for storing TNT under water or any other fluid.  It
is quite stable in air and presents no particular hazard 
if you don't eat it.

TNT is a bit too brittle to cut with a knife.  You might chip
some off or you could partially melt the block on a steam
bath.  Charges are usually fashioned from TNT by casting the
melted material below 100 deg C or by compressing the powder.
The cast material is not cap sensitive, but I can't really
recommend grinding the stuff despite its low sensitivity.

I don't recognize the origin of your post. How are the jails
in your part of the world?

Jerry (Ico)

From: Henry Spencer <henry@zoo.toronto.edu>
Newsgroups: sci.space.tech
Subject: Re: frozen H and O
Date: Thu, 6 Nov 1997 15:04:07 GMT

In article <19971031230001.SAA11549@ladder01.news.aol.com>,
Guff12345 <guff12345@aol.com> wrote:
>Ran across the term "slush hydrogen", what is it?  Is there slush Oxygen?

Slush hydrogen is just what you think, a slush of solid hydrogen in liquid
hydrogen.  It's a bit denser and has better cooling capacity.

There has been little interest in slush oxygen because oxygen is already
dense enough to keep most people happy.  The possibility exists.

>Has using solid (frozen) H and O ever been considered?

Not very seriously.  Liquids are much easier to handle.  Solid hydrogen
actually has about the consistency of butter, which gives you the worst
of both worlds.

>If you put blocks of frozen H and O together and then squeeze do they react
> once they melt?

Not unless you add a spark.  Note also that they don't melt simultaneously:
the hydrogen will boil long before the oxygen starts to melt.  (Meanwhile,
mind you, you will have a very dangerous explosive on your hands.)

> Would they make a good bomb
> material for conventional warfare (higher ISP means bigger boom)?

No.  The performance advantage is modest and the handling problems are
unacceptable.  The choice of explosives for conventional warfare is
dominated by secondary issues like safety and ease of manufacturing;
maximizing sheer explosive power is seldom very important.  (The reason
why TNT, in particular, was historically so popular is not that it's
tremendously powerful, but that it is fairly cheap to make and has one
property that's very convenient for casting:  it melts below 100C but is
stable up to well above 100C, so you can melt it using steam without risk
of overheating it.)
--
If NT is the answer, you didn't                 |     Henry Spencer
understand the question.  -- Peter Blake        | henry@zoo.toronto.edu

From: glhurst@onr.com (Gerald L. Hurst)
Newsgroups: alt.engr.explosives
Subject: Re: Electronic detonators?
Date: 31 Dec 1997 02:10:39 GMT

Cast TNT is not sensitive to a blasting cap, but the powdered material
shoots very well.  Cap-sensitive charges can be made by pressing
the ground material to near crystal density.

I once succeeded in making cap-sensitive cast charges but they
lost their sensitivity on storage.

Small (1 lb)  cast charges of either TNT or tritonal also fail to shoot
properly with a 50 gram tetryl primer but larger charges (5 lb) perform
quite well with the same initiator.

Jerry (Ico)

In article <34a8c95a.1233663@news.mira.net.au>, riordan@werple.net.au
(Roger Riordan) says:

>Detonators did not (in the 50's) set off TNT directly.  Detonator was
>placed in a primer (~1" dia * 1" long, tapered, I think), which in
>turn fitted into a hole cast in the slab of TNT.  TNT is hard to set
>off; told us in the army a rifle bullet would not set it off.  And
>from what I have read here a detonator would be wasted on flash
>powder; it goes off all too easily.