From: glhurst@onr.com (Gerald L. Hurst)
Newsgroups: rec.pyrotechnics
Subject: Re: "Imploding buildings" article in Scientific American
Date: 15 Sep 1995 20:23:01 GMT
Organization: Consulting Chemist

In article <43bdru$986@news.doit.wisc.edu>, djmullen@facstaff.wisc.edu 
(David Mullenix) says:

>One thing puzzles me: the caption to one picture says that sticks of 
>dynamite were broken, and blasting caps were inserted.  Is this how
>you get quarter sticks of dynamite?  Just snap a piece off a full
>sized stick?

In the field we always cut them with a knife against 
a piece of wood. Most dynmite sticks don't snap well 
because of the flexible paper wrapping.  There are 
some explosive compositions, loosly referred to as 
"dynamite," which are hard in composition. I personally
consider most dynamites as second-rate candidates for
controlled building demolition. Perhaps the press 
merely assumes that the explosives are NG products.

Another remote possibility would be that they use so-called
"military dynamite" or "Hercules medium velocity dynamite"
which is actually a military, non-NG explosive packaged
on a standard dynamite production line. I say "remote"
because the performance of this material is also rather 
mediocre compared to other RDX based explosives because of 
the low density as packaged.

Jerry

From: glhurst@onr.com (Gerald L. Hurst)
Newsgroups: alt.engr.explosives
Subject: Re: >>>Blasting Caps<<<
Date: 2 May 1996 08:16:10 GMT

In article <4m8d58$9ue@ccnet3.ccnet.com>, berniew@ccnet.com (Bernie
Willis) says:

>I have heard that dynamite can be detonated by a rifle bullet strike.
>Is that true?
>I saw a notice somewhere about a "dynamite shoot" target event.
>No problem for the judges scoring hits and misses!

Yes indeed, it goes boom with a bullet and it doesn't need to be 
a very high-powered one either. That's what's nice about many newer
explosives - they mostly shrug off even the larger caliber stuff 
like .30-06.  A pipsqueak .22 can set off dynamite.

The real test is to shoot the explosive in a sealed 2" steel pipe 
nipple with a .30 cal rifle. The more stable explosives survive 
this test most of the time.  I said "most of the time."  It's a
statistical sort of thing.

Jerry (Ico) 

From: glhurst@onr.com (Gerald L. Hurst)
Newsgroups: rec.pyrotechnics
Subject: Re: M - 80 power level ?
Date: 11 Dec 1996 22:12:28 GMT

In article <32AED273.5202@Bridge-City.com>, "Lloyd E. Sponenburgh"
<lloyds@Bridge-City.com> says:

>flashmax@aol.com wrote:
>> 
>> On HE and fireballs,
>>    I once had access to 10 sticks of 60% gelatin dynomite (5 # per stick
>
>FIVE POUNDS per stick?  REALLY!  How _long_ were these 'sticks' of 
>Dynomite (sic)?  Were they the 'traditional' diameter?  If so, WHAT was 
>their diameter?
>
>Five POUNDS per stick....  Wow!

There is nothing unusual about 5-pounde HE charges, although there's
not much dynamite per se around any more. The legal limit on dynamite
cartridge size used to be 65 lbs with a diameter of 12 inches.  The
most common large sizes were 4-6 inches in diameter.  The 1-1/4X8"
sticks were popular movie images symbolizing dynamite.  Serious
quarry work required large bore holes and large charges to fill them.

Jerry (Ico)

Subject: Re: Explosive SAWDUST!! How to make....
From: glhurst@onr.com (Gerald L. Hurst)
Date: Nov 23 1996
Newsgroups: rec.pyrotechnics

In article <574vt4$ld@news.terminus.com>, Spamo Blamo <spamo@spam.com> says:

>Actually the original form of dynamite were made from sawdust soaked
>with nitroglycerin.  The sawdust would make it less sensitive to
>motion.  The only problem is that the old dynamite would start sweating
>nitroglycerin, and then it would become dangerous if handled.  Now they
>use a type of gelatin instead of sawdust because it's more stable.

Actually, Nobel made both forms of NG explosives, the dynamites (NG in
kieselguhr in straight form) and blasting gelatin which he did not
invent but to which he quickly obtained the rights.

Over the years, both gelatins and so-called dynamites often contained
sawdust or analogous materials such as bagasse or apricot pitts or
whatever fuel was available at a low price.  These cellulosic materials
functioned both as absorbants and as oxygen balancers to match the added
sodium nitrate or ammonium nitrate.  In many formulations, the main 
source of heaving energy came from AN or SN plus cellulosic materials 
with just enough NG to drive the reaction in a bore hole.  At the bottom
of the list was "stumping dynamite," which had a 20% rating on the 
straight  dynamite scale.  In the field you mainly encountered 40% and
60% strength mixes with an occasional 75% batch.  These numbers 
reflected supposed ballistic mortar "equivalent" strengths - not actual
NG concentrations.  In real life, a straight 60% dynamite would have
shot the pants off the equivalent AN dynamite in applications requiring
high brisance from small charges such as in the secondary blasting of
boulders.

Sweating was a problem with most NG materials if they were stored too
long under bad conditions.  Usually, however, this just meant you were
liable to get an NG headache from absorption through the skin.  I 
always used a glove or at least a sheet of paper in handling the old
stuff to save on aspirin:)

Jerry (Ico)

The king of these NG explosives was the relatively rare 90% gelatin, 
which saw use in higher priced situations that called for brisance and
a lot of energy.  Such formulations were often used in oil well
shooting where maximum power and water-proofness were needed.

Subject: Re: ANFOS
From: glhurst@onr.com (Gerald L. Hurst)
Date: Jan 30 1997
Newsgroups: alt.engr.explosives

In article <mbA2fGANHn7yEw9D@pygmy.demon.co.uk>, scoop
<mail@pygmy.demon.co.uk> says:

>Wot...Dynamite with no NG is not Dynamite.
>
>Dynamite is a tradename of Nobel Explosives Sweden. Alfred Bernhard
>Nobel (yep the bloke who started the Nobel Peace Prize), invented
>Dynamite as a safe way to carry and use Nitroglycerin. He was an
>inventer and the owner of one of the largest NG factories in Sweden. 
>
>One of the factories is now a museum and well worth a visit. If military
>Dynamite has no NG it is just called, HE.
>
>"Enough history for to day, Weeks and Hurst will write 100 times,
>"Dynamite with no NG is not Dynamite", before next lesson.

"Dynamite" is a generic term - it is not a registered trademark in 
the US.

There are at least two non-NG military dynamites:

1. Dynamite, Low Velocity, Picatinny Arsenal (LVD)

2. Dynamite, Medium Velocity, Hercules (MVD)

Both of these cartridge materials are or can be packaged on 
standard dynamite machinery and neither of them contains NG. 

In the strictest sense the word "dynamite" would be used to
refer only to explosives made by absorbing NG in kieselguhr.
In practice most NG products are much more complicated
mixtures in which the majority of the energy may be provided
by other materials, mainly inorganic nitrate/fuel mixtures
with just enough NG to sensitize the composition. These 
materials have various descriptive names that indicate to
some extent their compositions (e.g., "ammonia gelatin"), 
but are usually simply referred to simply as "dynamites."

The military folks do not like NG products because they are 
too sensitive to impact.  Therefore, they make non-NG stick
explosives which perform like dynamite but are less sensitive.
Whether you, I or Nobel like it or not, these explosives are
formally listed by the government as "dynamites."

If you will take a peek in a good dictionary, you will find
one or more definitions of "dynamite" which include non-NG
blasting materials.

Jerry (Ico)