--I've been trying for ages to get my .177 cal mortar to shoot a
pellet more than a foot. I'm using FFG which is the finest powder available
locally. What I need, I think, is the stuff that's normally packed into
firecrackers. Now' I've toyed with the idea of making a brass mortar and
pestel to grind the FFG powder into something finer but I thot I'd better
ask here B4 becoming a candidate for a Darwin Award.
--Any useful advice appreciated!

--
"Steamboat Ed" Haas : Come see my stuff
Hacking the Trailing Edge! : at Maker Faire!!
www.nmpproducts.com
---Decks a-wash in a sea of words---

"steamer" wrote in message
...
--I've been trying for ages to get my .177 cal mortar to shoot a
pellet more than a foot. I'm using FFG which is the finest powder
available
locally. What I need, I think, is the stuff that's normally packed into
firecrackers. Now' I've toyed with the idea of making a brass mortar and
pestel to grind the FFG powder into something finer but I thot I'd better
ask here B4 becoming a candidate for a Darwin Award.
--Any useful advice appreciated!

Get a ceramic mortar and pestle from a gourmet cooking supply shop, and do a
match-head-sized lump at a time. Wear face protection and gloves. Keep your
supply and container for ground powder eight or ten feet away, and keep
dumping each little bit into the container.

I've done it when I couldn't get good primer powder for a flintlock rifle.
I've also ground up homemade powder this way, when I mixed it wet and dried
it into little lumps. I never had any drama from it. Patience is better than
drama.

--
Ed Huntress

steamer wrote:
--I've been trying for ages to get my .177 cal mortar to shoot a
pellet more than a foot. I'm using FFG which is the finest powder available
locally. What I need, I think, is the stuff that's normally packed into
firecrackers. Now' I've toyed with the idea of making a brass mortar and
pestel to grind the FFG powder into something finer but I thot I'd better
ask here B4 becoming a candidate for a Darwin Award.
--Any useful advice appreciated!


Try a percussion cap instead of powder.

Ed Huntress wrote:
"steamer" wrote in message
...
--I've been trying for ages to get my .177 cal mortar to shoot a
pellet more than a foot. I'm using FFG which is the finest powder
available
locally. What I need, I think, is the stuff that's normally packed
into firecrackers. Now' I've toyed with the idea of making a brass
mortar and pestel to grind the FFG powder into something finer but I
thot I'd better ask here B4 becoming a candidate for a Darwin Award.
--Any useful advice appreciated!

Get a ceramic mortar and pestle from a gourmet cooking supply shop,
and do a match-head-sized lump at a time. Wear face protection and
gloves. Keep your supply and container for ground powder eight or ten
feet away, and keep dumping each little bit into the container.

I've done it when I couldn't get good primer powder for a flintlock
rifle. I've also ground up homemade powder this way, when I mixed it
wet and dried it into little lumps. I never had any drama from it.
Patience is better than drama.

--
Ed Huntress

Additionally , use a grounded strap on your wrist and all containers and
work surfaces . A static spark can kill you ! Wear cotton clothing - less
likely to build a static charge - and thin leather gloves for both
sensitivity and burn protection . BP is originally granulated while still
damp , with the exception of FFFFG , which is pulverized in a ball mill .
Every accident I've seen (only a few ,thankfully) involving HE and other
explosives/pyrothechnics has been caused by static discharge ... or sheer
stupidity , as in "hole ma beer an' watch this" .
--
Snag
"Still got ten , two , and two ."

On May 21, 12:15*pm, steamer wrote:
* * * * --I've been trying for ages to get my .177 cal mortar to shoot a
pellet more than a foot. I'm using FFG which is the finest powder available
locally. What I need, I think, is the stuff that's normally packed into
firecrackers. Now' I've toyed with the idea of making a brass mortar and
pestel to grind the FFG powder into something finer but I thot I'd better
ask here B4 becoming a candidate for a Darwin Award.
* * * * --Any useful advice appreciated!

--
* * * * "Steamboat Ed" Haas * * * * : *Come see my stuff *
* * * * Hacking the Trailing Edge! *: *at Maker Faire!!
* * * * * * * * * * * * *www.nmpproducts.com
* * * * * * * * * *---Decks a-wash in a sea of words---

Trying to get flash powder to propel any sort of a projectile is a
good way to end up missing bits of yourself, or ending up with holes
and metallic attachments where you don't want them. I've used primers
to propel lead air rifle pellets in regular firearms, THAT works.
Unfortunately, primer costs have risen to the point where it's kind of
silly to do so. An air rifle works sooo much better for that sort of
thing.

FFFFg is what you want, you might be able to convert some of your
coarser stuff by sandwiching a smidge between two sheets of paper and
running a cylindrical glass bottle over it. Don't be surprised if an
air rifle pellet doesn't work too well, they have a tendancy to blow
out at the heads. A round ball works better. .177 round balls CAN be
had, too.

Here's Pedersoli's take on what you want to do:
http://www.cabelas.com/cabelas/en/te...box.jsp.form23

But again, you can buy an airgun a whole lot cheaper and it'll even
have better ballistics than that.

Stan

On 5/21/2010 11:54 AM, Snag wrote:

or sheer stupidity , as in "hole ma beer an' watch this" .

Which is the basis for a respectable number of YouTube's videos... G


Jon

"steamer" wrote in message
...
--I've been trying for ages to get my .177 cal mortar to shoot a
pellet more than a foot. I'm using FFG which is the finest powder
available
locally. What I need, I think, is the stuff that's normally packed into
firecrackers. Now' I've toyed with the idea of making a brass mortar and
pestel to grind the FFG powder into something finer but I thot I'd better
ask here B4 becoming a candidate for a Darwin Award.
--Any useful advice appreciated!

--
"Steamboat Ed" Haas : Come see my stuff
Hacking the Trailing Edge! : at Maker Faire!!
www.nmpproducts.com
---Decks a-wash in a sea of words---

The pellet is too loose in the bore, patch it.

On May 21, 2:54*pm, "Snag" wrote:
Ed Huntress wrote:
"steamer" wrote in message
...
--I've been trying for ages to get my .177 cal mortar to shoot a
pellet more than a foot. I'm using FFG which is the finest powder
available
locally. What I need, I think, is the stuff that's normally packed
into firecrackers. Now' I've toyed with the idea of making a brass
mortar and pestel to grind the FFG powder into something finer but I
thot I'd better ask here B4 becoming a candidate for a Darwin Award.
--Any useful advice appreciated!

Get a ceramic mortar and pestle from a gourmet cooking supply shop,
and do a match-head-sized lump at a time. Wear face protection and
gloves. Keep your supply and container for ground powder eight or ten
feet away, and keep dumping each little bit into the container.

I've done it when I couldn't get good primer powder for a flintlock
rifle. I've also ground up homemade powder this way, when I mixed it
wet and dried it into little lumps. I never had any drama from it.
Patience is better than drama.

--
Ed Huntress

Additionally , use a grounded strap on your wrist and all containers and
work surfaces . A static spark can kill you ! Wear cotton clothing - less
likely to build a static charge - and thin leather gloves for both
sensitivity and burn protection . BP is originally granulated while still
damp , with the exception of FFFFG , which is pulverized in a ball mill .
* Every accident I've seen (only a few ,thankfully) involving HE and other
explosives/pyrothechnics has been caused by static discharge ... or sheer
stupidity , as in "hole ma beer an' watch this" .
--
Snag
"Still got ten , two , and two
For two years during the Viet Nam war I worked at the Cornhusker Army
Ammunition plant in Grand Island, Nebraska. One of the jobs on the
bomb making line was to take 50# boxes of TNT (sometimes Ammonium
Nitrate) off a conveyor line and unbox the sacks with the explosives
and dump them in a hopper where the contents dropped into huge wheeled
carts a floor below. Usually these bags were waxed paper. In addition
to all cotton clothes and special shoes and gloves we took all kinds
of precautions to prevent static electricity. One day two truckloads
of TNT cames in that were packed differently. They were wrapped in
plastic instead of the usual waxed paper. The station that unloaded
the first bag noticed a static electric spark when they emptied the
bag. Luckily no explosion! The lead man immediately hit the switch to
stop the conveyor line and called the foreman. The foreman called the
line supervisor and the safety man. The line supervisor we could keep
the bags in contact with the metal hopper while emptying and they
would not spark. The safety man was not going to say NO to the line
supervisor. However by this time the Union Steward had notified the
Union Headquarters about the problem and the Union honchos told her to
shut down the line. We all walked off because we knew it was dangerous
to continue unloading those plastic bags. Eleven million pounds of TNT
from that shipment was returned to DuPont to be repackaged. During a
follow up by the Union it was said that this 11 million pounds had
been rejected by another arsenal because of the spark hazard. Instead
of repacking then someone in the food chain decided to send it to us
because they thought our Union people would cave in. A perfect example
of just how stupid decisions are made by management all the time.

DL

On 2010-05-21, steamer wrote:
--I've been trying for ages to get my .177 cal mortar to shoot a
pellet more than a foot. I'm using FFG which is the finest powder available
locally. What I need, I think, is the stuff that's normally packed into
firecrackers.

I'm not at all sure that I would trust that. It has a *lot*
faster burning rate than black or smokeless powders. You might as well
put a drop of nitroglycerine in it. :-)

Now' I've toyed with the idea of making a brass mortar and
pestel to grind the FFG powder into something finer but I thot I'd better
ask here B4 becoming a candidate for a Darwin Award.

As already suggested -- seriously minimize the amount which you
are working with. And avoid metals in the mortar and pestle. (But for
the .177 caliber mortar, you *do* want metal, of course. :-)

How long is the barrel in the mortar? I would be tempted to use
a small pinch of Bullseye smokeless for the fast burning. But make sure
that the wall thickness is sufficient to handle the possible pressure
peaks.

Good Luck,
DoN.

--
Email: | Voice (all times): (703) 938-4564
(too) near Washington D.C. | http://www.d-and-d.com/dnichols/DoN.html
--- Black Holes are where God is dividing by zero ---

On May 21, 6:20*pm, TwoGuns wrote:


We all walked off because we knew it was dangerous
to continue unloading those plastic bags. Eleven million pounds of TNT
from that shipment was returned to DuPont to be repackaged. During a
follow up by the Union it was said that this 11 million pounds had
been rejected by another arsenal because of the spark hazard. Instead
of repacking then someone in the food chain decided to send it to us
because they thought our Union people would cave in. A perfect example
of just how stupid decisions are made by management all the time.

DL

Does make one wonder how shipping 11 million lbs back to Du Pont and
having Du Pont unpackage and repackage the TNT, and then reship back
to Nebraska to be unpackaged again is safer than just unpackaging the
TNT once.

Dan

On May 21, 8:02*pm, "DoN. Nichols" wrote:
On 2010-05-21, steamer wrote:

* *--I've been trying for ages to get my .177 cal mortar to shoot a
pellet more than a foot. I'm using FFG which is the finest powder available
locally. What I need, I think, is the stuff that's normally packed into
firecrackers.

* * * * I'm not at all sure that I would trust that. *It has a *lot*
faster burning rate than black or smokeless powders. *You might as well
put a drop of nitroglycerine in it. :-)

I assume perhaps incorrectly that your mortar has a barrel length that
is maybe ten times the bore. Probably less than 2 inches. So you are
going to have to use something that burns fast. But I am a bit
skeptical of the stuff in firecrackers. It is intended to explode
with minimal containment.


* * * * * * * Now' I've toyed with the idea of making a brass mortar and
pestel to grind the FFG powder into something finer but I thot I'd better
ask here B4 becoming a candidate for a Darwin Award.

I think using a brass mortar and pestle is the way to go. You can and
should ground both of them. I would stay away from ceramic is it is
usually a good insulator. And of course stay away from steel.

* * * * As already suggested -- seriously minimize the amount which you
are working with. *And avoid metals in the mortar and pestle. (But for
the .177 caliber mortar, you *do* want metal, of course. :-)

* * * * How long is the barrel in the mortar? *I would be tempted to use
a small pinch of Bullseye smokeless for the fast burning. *But make sure
that the wall thickness is sufficient to handle the possible pressure
peaks.

* * * * Good Luck,
* * * * * * * * DoN.

--
*Email: * * | Voice (all times): (703) 938-4564
* * * * (too) near Washington D.C. |http://www.d-and-d.com/dnichols/DoN.html
* * * * * *--- Black Holes are where God is dividing by zero ---

Not to worry about static and TNT. You can play a blowtorch on it and it will only melt and burn,
not detonate. Same with dynamite, except it will only make a nice fire, not melt.

Bob Swinney
wrote in message
...
On May 21, 6:20 pm, TwoGuns wrote:


We all walked off because we knew it was dangerous
to continue unloading those plastic bags. Eleven million pounds of TNT
from that shipment was returned to DuPont to be repackaged. During a
follow up by the Union it was said that this 11 million pounds had
been rejected by another arsenal because of the spark hazard. Instead
of repacking then someone in the food chain decided to send it to us
because they thought our Union people would cave in. A perfect example
of just how stupid decisions are made by management all the time.

DL

Does make one wonder how shipping 11 million lbs back to Du Pont and
having Du Pont unpackage and repackage the TNT, and then reship back
to Nebraska to be unpackaged again is safer than just unpackaging the
TNT once.

Dan

"I assume perhaps incorrectly that your mortar has a barrel length that
is maybe ten times the bore. Probably less than 2 inches. So you are
going to have to use something that burns fast. But I am a bit
skeptical of the stuff in firecrackers. It is intended to explode
with minimal containment."

Not sure about that. Stuff in firecrackers is class 2 explosive, the same as black powder. It is
called "flash powder" because of substances which make it flash into light as it burns; not burn
with any more accelerated rate than any other powder of the same granulation. An explosive that
detonates with minimal or no confinemant detonates (extremely rapid combustion) and requires
mechanical shock to start the process.

Bob Swinney



wrote in message
...
On May 21, 8:02 pm, "DoN. Nichols" wrote:
On 2010-05-21, steamer wrote:

--I've been trying for ages to get my .177 cal mortar to shoot a
pellet more than a foot. I'm using FFG which is the finest powder available
locally. What I need, I think, is the stuff that's normally packed into
firecrackers.

I'm not at all sure that I would trust that. It has a *lot*
faster burning rate than black or smokeless powders. You might as well
put a drop of nitroglycerine in it. :-)



Now' I've toyed with the idea of making a brass mortar and
pestel to grind the FFG powder into something finer but I thot I'd better
ask here B4 becoming a candidate for a Darwin Award.

I think using a brass mortar and pestle is the way to go. You can and
should ground both of them. I would stay away from ceramic is it is
usually a good insulator. And of course stay away from steel.

As already suggested -- seriously minimize the amount which you
are working with. And avoid metals in the mortar and pestle. (But for
the .177 caliber mortar, you *do* want metal, of course. :-)

How long is the barrel in the mortar? I would be tempted to use
a small pinch of Bullseye smokeless for the fast burning. But make sure
that the wall thickness is sufficient to handle the possible pressure
peaks.

Good Luck,
DoN.

--
Email: | Voice (all times): (703) 938-4564
(too) near Washington D.C. |http://www.d-and-d.com/dnichols/DoN.html
--- Black Holes are where God is dividing by zero ---

On Fri, 21 May 2010 20:43:11 -0500, "Robert Swinney"
wrote:

Not to worry about static and TNT. You can play a blowtorch on it and it will only melt and burn,
not detonate. Same with dynamite, except it will only make a nice fire, not melt.

Bob Swinney

Right about TNT, C4, PETN, RDX, tetrytol and other military HE but
wrong about dynamite.

Don,

Wrong about dynamite in what way? Are you saying it won't melt or won't burn? In simplistic terms,
dynamite is desensitized nitroglycerine, requiring a mechanical shock to cause detonation

Bob Swinney
"Don Foreman" wrote in message
news On Fri, 21 May 2010 20:43:11 -0500, "Robert Swinney"
wrote:

Not to worry about static and TNT. You can play a blowtorch on it and it will only melt and burn,
not detonate. Same with dynamite, except it will only make a nice fire, not melt.

Bob Swinney

Right about TNT, C4, PETN, RDX, tetrytol and other military HE but
wrong about dynamite.

In article ,
" wrote:

On May 21, 6:20*pm, TwoGuns wrote:


We all walked off because we knew it was dangerous
to continue unloading those plastic bags. Eleven million pounds of TNT
from that shipment was returned to DuPont to be repackaged. During a
follow up by the Union it was said that this 11 million pounds had
been rejected by another arsenal because of the spark hazard. Instead
of repacking then someone in the food chain decided to send it to us
because they thought our Union people would cave in. A perfect example
of just how stupid decisions are made by management all the time.

DL

Does make one wonder how shipping 11 million lbs back to Du Pont and
having Du Pont unpackage and repackage the TNT, and then reship back
to Nebraska to be unpackaged again is safer than just unpackaging the
TNT once.

The intent was to convince du Pont not to do that again.

Joe Gwinn

On May 21, 7:42*pm, " wrote:
On May 21, 6:20*pm, TwoGuns wrote:

We all walked off because we knew it was dangerous
to continue unloading those plastic bags. Eleven million pounds of TNT
from that shipment was returned to DuPont to be repackaged. During a
follow up by the Union it was said that this 11 million pounds had
been rejected by another arsenal because of the spark hazard. Instead
of repacking then someone in the food chain decided to send it to us
because they thought our Union people would cave in. A perfect example
of just how stupid decisions are made by management all the time.

DL

Does make one wonder how shipping 11 million lbs back to Du Pont and
having Du Pont unpackage and repackage the TNT, and then reship back
to Nebraska to be unpackaged again is safer than just unpackaging the
TNT once.

* * * * * * * * * * * * * * * * * * * * * * * * * * * * *Dan

If we would have unpacked and used the TNT on the production site
there was about 100,000 pounds of TNT in that one small building. The
big danger in our location was dust. Think a grain dust explosion
multiplied about 1,000 times with TNT dust. By shipping it off to
another location it could have been repacked in more isolated location
with smaller amounts of explosives nearby. Hell they probably just
burned it anyway. Thatwas safer and probably cheaper.

DL

It is highly unlikely a dust explosion, even of TNT dust, would set off the entire dump. One of the
attributes of TNT is that it is so stable that a single shell fired into a dump of similar shells
will not cause a dump event. This is for TNT loaded projectiles only. All bets are off if there
were primers present as with fully loaded fixed artillery munitions.

Bob (don't include me any of the tests, however) Swinney
"TwoGuns" wrote in message
...
On May 21, 7:42 pm, " wrote:
On May 21, 6:20 pm, TwoGuns wrote:

We all walked off because we knew it was dangerous
to continue unloading those plastic bags. Eleven million pounds of TNT
from that shipment was returned to DuPont to be repackaged. During a
follow up by the Union it was said that this 11 million pounds had
been rejected by another arsenal because of the spark hazard. Instead
of repacking then someone in the food chain decided to send it to us
because they thought our Union people would cave in. A perfect example
of just how stupid decisions are made by management all the time.

DL

Does make one wonder how shipping 11 million lbs back to Du Pont and
having Du Pont unpackage and repackage the TNT, and then reship back
to Nebraska to be unpackaged again is safer than just unpackaging the
TNT once.

Dan

If we would have unpacked and used the TNT on the production site
there was about 100,000 pounds of TNT in that one small building. The
big danger in our location was dust. Think a grain dust explosion
multiplied about 1,000 times with TNT dust. By shipping it off to
another location it could have been repacked in more isolated location
with smaller amounts of explosives nearby. Hell they probably just
burned it anyway. Thatwas safer and probably cheaper.

DL

On Sat, 22 May 2010 07:20:51 -0500, "Robert Swinney"
wrote:

Don,

Wrong about dynamite in what way? Are you saying it won't melt or won't burn? In simplistic terms,
dynamite is desensitized nitroglycerine, requiring a mechanical shock to cause detonation

Dynamite is a whole lot touchier than the other high explosives.
Military demo guys won't mess with dynamite if there's any way to
avoid it. There is such a thing as "military dynamite" but it is not
based on nitroglycerine.

Old dynamite can be disposed of by burning, but you don't want to be
anywhere near that bonfire because there is a chance that it will
detonate if it's old or if there's enough of it.

Actually, the others can go if there's enough of it and it gets hot
enough. Ammonium nitrate is notoriously hard to detonate. Military
40-lb cratering charges had cap wells but we were taught to add a bit
of encouragement with a pingpong ball sized gob of C-4 around the cap.
Yet, you undoubtedly have read about the Texas City Disaster where a
fire aboard a shipload of ammonium nitrate resulted in detonation.
http://en.wikipedia.org/wiki/Texas_City_Disaster


Bob Swinney
"Don Foreman" wrote in message
news On Fri, 21 May 2010 20:43:11 -0500, "Robert Swinney"
wrote:

Not to worry about static and TNT. You can play a blowtorch on it and it will only melt and burn,
not detonate. Same with dynamite, except it will only make a nice fire, not melt.

Bob Swinney

Right about TNT, C4, PETN, RDX, tetrytol and other military HE but
wrong about dynamite.

On 21 May 2010 18:15:26 GMT, steamer wrote:

--I've been trying for ages to get my .177 cal mortar to shoot a
pellet more than a foot. I'm using FFG which is the finest powder available
locally. What I need, I think, is the stuff that's normally packed into
firecrackers. Now' I've toyed with the idea of making a brass mortar and
pestel to grind the FFG powder into something finer but I thot I'd better
ask here B4 becoming a candidate for a Darwin Award.
--Any useful advice appreciated!

NO!!!!

BP will ignite under compression, no matter what is compressing it.

You need to wet it down completely..let it turn in mud...then when its
ALMOST dry...break it down into finer particles...then let it dry
completely.

Or get a can of 4X priming powder used in flintlocks and save yourself
mondo trouble.

Gunner

--


"First Law of Leftist Debate
The more you present a leftist with factual evidence
that is counter to his preconceived world view and the
more difficult it becomes for him to refute it without
losing face the chance of him calling you a racist, bigot,
homophobe approaches infinity.

This is despite the thread you are in having not mentioned
race or sexual preference in any way that is relevant to
the subject." Grey Ghost

On Sat, 22 May 2010 00:15:23 -0500, Don Foreman
wrote:

On Fri, 21 May 2010 20:43:11 -0500, "Robert Swinney"
wrote:

Not to worry about static and TNT. You can play a blowtorch on it and it will only melt and burn,
not detonate. Same with dynamite, except it will only make a nice fire, not melt.

Bob Swinney

Right about TNT, C4, PETN, RDX, tetrytol and other military HE but
wrong about dynamite.

Big Gold Star

For those that dont know..dynamite is nitroglcerin in a diatomasious
earth filler (think finely ground kitty litter)

Nitro can and DOES pool in boxes that are not turned over regularly, and
gets hyper sensitive with age and ULTRA sensitive if frozen and then
thawed out.

Gunner, one time shooter for the Atlas Powder Company (for a half a
year) and rather familiar with military uses of ultra high velocity high
prisance compounds


--


"First Law of Leftist Debate
The more you present a leftist with factual evidence
that is counter to his preconceived world view and the
more difficult it becomes for him to refute it without
losing face the chance of him calling you a racist, bigot,
homophobe approaches infinity.

This is despite the thread you are in having not mentioned
race or sexual preference in any way that is relevant to
the subject." Grey Ghost

Don sez:

"Old dynamite can be disposed of by burning, but you don't want to be
anywhere near that bonfire because there is a chance that it will
detonate if it's old or if there's enough of it."

Explosives, in general, are "touchy" when burned in large quantities. Who knows? Perhaps in large
fires, such as the Texas City ammonium nitrate disaster, there was some initiator within the fire
(maybe a super-heated steam or air line) that acted as detonator. In all likelihood, the ship's
fuel oil contributed to an explosive mixture of ANFO. The fire raged for many hours before the
ultimate explosion.

Some 50 years ago, the city of Hot Springs, AR was burning a large quantity of old dynamite -
supposedly safely. It blew and killed several people. The dyno was being burned in an area near
the police shooting range. Theory has it that an old pistol cartridge may have been in the ground
under the fire.

Bob Swinney


"Don Foreman" wrote in message
...
On Sat, 22 May 2010 07:20:51 -0500, "Robert Swinney"
wrote:

Don,

Wrong about dynamite in what way? Are you saying it won't melt or won't burn? In simplistic terms,
dynamite is desensitized nitroglycerine, requiring a mechanical shock to cause detonation

Dynamite is a whole lot touchier than the other high explosives.
Military demo guys won't mess with dynamite if there's any way to
avoid it. There is such a thing as "military dynamite" but it is not
based on nitroglycerine.


Actually, the others can go if there's enough of it and it gets hot
enough. Ammonium nitrate is notoriously hard to detonate. Military
40-lb cratering charges had cap wells but we were taught to add a bit
of encouragement with a pingpong ball sized gob of C-4 around the cap.
Yet, you undoubtedly have read about the Texas City Disaster where a
fire aboard a shipload of ammonium nitrate resulted in detonation.
http://en.wikipedia.org/wiki/Texas_City_Disaster


Bob Swinney
"Don Foreman" wrote in message
news On Fri, 21 May 2010 20:43:11 -0500, "Robert Swinney"
wrote:

Not to worry about static and TNT. You can play a blowtorch on it and it will only melt and burn,
not detonate. Same with dynamite, except it will only make a nice fire, not melt.

Bob Swinney

Right about TNT, C4, PETN, RDX, tetrytol and other military HE but
wrong about dynamite.

Gunner Asch wrote in
:

On 21 May 2010 18:15:26 GMT, steamer wrote:

--I've been trying for ages to get my .177 cal mortar to shoot a
pellet more than a foot. I'm using FFG which is the finest powder
available locally. What I need, I think, is the stuff that's normally
packed into firecrackers. Now' I've toyed with the idea of making a
brass mortar and pestel to grind the FFG powder into something finer
but I thot I'd better ask here B4 becoming a candidate for a Darwin
Award.
--Any useful advice appreciated!

NO!!!!

BP will ignite under compression, no matter what is compressing it.

You need to wet it down completely..let it turn in mud...then when its
ALMOST dry...break it down into finer particles...then let it dry
completely.

Or get a can of 4X priming powder used in flintlocks and save yourself
mondo trouble.

When I was a kid, we used to visit the duPont museum on the Brandywine
River near Wilmington. It was very well done, and you could walk along
the river where they had the remains of several blackpowder grinding
buildings. They each had three heavy stone walls, with the 4th side
along the river. The roof sloped towards the river as well. That way
when they blew up, all the burning wood got blown into the river. Each
building had a plaque on it: Built such & such year, blew up several
years later, rebuilt, blew up several years later, rebuilt, blew up, etc.

Doug White

Doug sez:

"When I was a kid, we used to visit the DuPont museum on the Brandywine
River near Wilmington. It was very well done, and you could walk along
the river where they had the remains of several blackpowder grinding
buildings. . . . ."

The book "The Big Bang" has pictures of those powder mill buildings along the Brandywine. BP was
ground with huge rotary stone mills. The general surmise is that some errant spark, not grinding
pressure, was the ever-present recipe for disaster. BP was ground wet to minimize the spark danger.
Ultimately, it had to dried, sevearly compounding the spark danger.

Bob Swinney

On Sun, 23 May 2010 08:17:11 -0500, "Robert Swinney"
wrote:

Don sez:

"Old dynamite can be disposed of by burning, but you don't want to be
anywhere near that bonfire because there is a chance that it will
detonate if it's old or if there's enough of it."

Explosives, in general, are "touchy" when burned in large quantities. Who knows? Perhaps in large
fires, such as the Texas City ammonium nitrate disaster, there was some initiator within the fire
(maybe a super-heated steam or air line) that acted as detonator. In all likelihood, the ship's
fuel oil contributed to an explosive mixture of ANFO. The fire raged for many hours before the
ultimate explosion.

Dad was plowing a rice field about 25 miles away from Texas City when
it went off. He said it sounded like a .30-06, just a flat, loud
crack. That land is flat as a pancake, and back then was empty. Not
much to generate the usual echos.

According to a long article in the American Legion magazine, the
Grandcamp's crew fought a smouldering paper bag fire in the hold by
battening down the hatches and pumping in live steam, which turned out
to be exactly the wrong action in this case. At one point before it
blew, the firehose streams were bouncing off the hull like a drop of
water on a hot griddle.

Apparently, the hold finally overpressured and the hatches blew off,
with a resulting very large golden cloud of AN, which then detonated.
An airplane circling the site far enough away to survive saw the cloud
before the explosion. Most of those killed had come down to watch
them fight the fire. One exception was a couple driving down the road
several miles away who were killed when a large piece of steel plate
fell out of the sky and sliced their car in half.

A former coworker told me of his father-in-law who was a dentist at
the time of the disaster. The man had the horrific job of trying to
identify remains from dental records. He never was able to practice
again.

Pete Keillor

Some 50 years ago, the city of Hot Springs, AR was burning a large quantity of old dynamite -
supposedly safely. It blew and killed several people. The dyno was being burned in an area near
the police shooting range. Theory has it that an old pistol cartridge may have been in the ground
under the fire.

Bob Swinney


"Don Foreman" wrote in message
.. .
On Sat, 22 May 2010 07:20:51 -0500, "Robert Swinney"
wrote:

Don,

Wrong about dynamite in what way? Are you saying it won't melt or won't burn? In simplistic terms,
dynamite is desensitized nitroglycerine, requiring a mechanical shock to cause detonation

Dynamite is a whole lot touchier than the other high explosives.
Military demo guys won't mess with dynamite if there's any way to
avoid it. There is such a thing as "military dynamite" but it is not
based on nitroglycerine.


Actually, the others can go if there's enough of it and it gets hot
enough. Ammonium nitrate is notoriously hard to detonate. Military
40-lb cratering charges had cap wells but we were taught to add a bit
of encouragement with a pingpong ball sized gob of C-4 around the cap.
Yet, you undoubtedly have read about the Texas City Disaster where a
fire aboard a shipload of ammonium nitrate resulted in detonation.
http://en.wikipedia.org/wiki/Texas_City_Disaster


Bob Swinney
"Don Foreman" wrote in message
news On Fri, 21 May 2010 20:43:11 -0500, "Robert Swinney"
wrote:

Not to worry about static and TNT. You can play a blowtorch on it and it will only melt and burn,
not detonate. Same with dynamite, except it will only make a nice fire, not melt.

Bob Swinney

Right about TNT, C4, PETN, RDX, tetrytol and other military HE but
wrong about dynamite.

On May 23, 9:25*am, Doug White wrote:



When I was a kid, we used to visit the duPont museum on the Brandywine
River near Wilmington. *It was very well done, and you could walk along
the river where they had the remains of several blackpowder grinding
buildings. *They each had three heavy stone walls, with the 4th side
along the river. *The roof sloped towards the river as well. *That way
when they blew up, all the burning wood got blown into the river. *Each
building had a plaque on it: *Built such & such year, blew up several
years later, rebuilt, blew up several years later, rebuilt, blew up, etc.

Doug White

Still there and still well done. Since you visited the Hagley Museum
they have restored the repair machine shop to about what it would have
been like in about 1870. All line shaft machine tools except for a
post drill and a treadle lathe. The machines are all operational and
the operation is demonstrated by volunteers. There are pictures on
line, but right now I can not find a site with pictures of all the
machines.

They have a some special events that might appeal to RCM members. The
car show will be Sept. 19th.

Dan

Pete Keillor wrote:

According to a long article in the American Legion magazine, the
Grandcamp's crew fought a smouldering paper bag fire in the hold by
battening down the hatches and pumping in live steam, which turned out
to be exactly the wrong action in this case. At one point before it
blew, the firehose streams were bouncing off the hull like a drop of
water on a hot griddle.


Was that American Legion article written back in the 70's? Just wondering, I seem to
remember reading it when I was a kid.

Wes

On Sun, 23 May 2010 19:41:59 -0400, Wes
wrote:

Pete Keillor wrote:

According to a long article in the American Legion magazine, the
Grandcamp's crew fought a smouldering paper bag fire in the hold by
battening down the hatches and pumping in live steam, which turned out
to be exactly the wrong action in this case. At one point before it
blew, the firehose streams were bouncing off the hull like a drop of
water on a hot griddle.


Was that American Legion article written back in the 70's? Just wondering, I seem to
remember reading it when I was a kid.

Wes

Sounds about right. It was quite a while ago.

Pete

Trivia re. the Texas City disaster:

Dan Rather, as a young Houston TV reporter, got his big career break from the event.

Bob Swinney
"Pete Keillor" wrote in message
...
On Sun, 23 May 2010 19:41:59 -0400, Wes
wrote:

Pete Keillor wrote:

According to a long article in the American Legion magazine, the
Grandcamp's crew fought a smouldering paper bag fire in the hold by
battening down the hatches and pumping in live steam, which turned out
to be exactly the wrong action in this case. At one point before it
blew, the firehose streams were bouncing off the hull like a drop of
water on a hot griddle.


Was that American Legion article written back in the 70's? Just wondering, I seem to
remember reading it when I was a kid.

Wes

Sounds about right. It was quite a while ago.

Pete

Robert Swinney wrote:
Trivia re. the Texas City disaster:

Dan Rather, as a young Houston TV reporter, got his big career break from the event.

I thought his big break came because he didn't report what he saw at
Dealey Plaza.

David

On Sun, 23 May 2010 19:08:15 -0500, "Robert Swinney"
wrote:

Trivia re. the Texas City disaster:

Dan Rather, as a young Houston TV reporter, got his big career break from the event.

Bob Swinney

I think you're thinking of Hurricane Carla. Rather was about 15 at
the time of Texas City.

Pete

"Pete Keillor" wrote in message
.. .
On Sun, 23 May 2010 19:41:59 -0400, Wes
wrote:

Pete Keillor wrote:

According to a long article in the American Legion magazine, the
Grandcamp's crew fought a smouldering paper bag fire in the hold by
battening down the hatches and pumping in live steam, which turned out
to be exactly the wrong action in this case. At one point before it
blew, the firehose streams were bouncing off the hull like a drop of
water on a hot griddle.


Was that American Legion article written back in the 70's? Just wondering, I seem to
remember reading it when I was a kid.

Wes

Sounds about right. It was quite a while ago.

Pete

Pete is right. I was mis-remembering another account of Rather's. Rather was born in 1931 - a bit
early to have reported on the 1947 TX City dock explosion.

Bob Swinney
"Pete Keillor" wrote in message
...
On Sun, 23 May 2010 19:08:15 -0500, "Robert Swinney"
wrote:

Trivia re. the Texas City disaster:

Dan Rather, as a young Houston TV reporter, got his big career break from the event.

Bob Swinney

I think you're thinking of Hurricane Carla. Rather was about 15 at
the time of Texas City.

Pete

"Pete Keillor" wrote in message
.. .
On Sun, 23 May 2010 19:41:59 -0400, Wes
wrote:

Pete Keillor wrote:

According to a long article in the American Legion magazine, the
Grandcamp's crew fought a smouldering paper bag fire in the hold by
battening down the hatches and pumping in live steam, which turned out
to be exactly the wrong action in this case. At one point before it
blew, the firehose streams were bouncing off the hull like a drop of
water on a hot griddle.


Was that American Legion article written back in the 70's? Just wondering, I seem to
remember reading it when I was a kid.

Wes

Sounds about right. It was quite a while ago.

Pete

--Thanks for all the advice gang. Sounds like the thing to do with
the powder I've got is to try grinding it wet with brass mortar and pestel.
This #4 flintlock (?) priming powder sounds like a good bet too; where would one
find that? Will have another look thru the Dixie catalog; they've got damn
near everything, yes?

--
"Steamboat Ed" Haas : Come see my stuff
Hacking the Trailing Edge! : at Maker Faire!!
www.nmpproducts.com
---Decks a-wash in a sea of words---

On 05/21/2010 03:20 PM, TwoGuns wrote:
On May 21, 2:54 pm, wrote:
Ed Huntress wrote:
wrote in message
...
--I've been trying for ages to get my .177 cal mortar to shoot a
pellet more than a foot. I'm using FFG which is the finest powder
available
locally. What I need, I think, is the stuff that's normally packed
into firecrackers. Now' I've toyed with the idea of making a brass
mortar and pestel to grind the FFG powder into something finer but I
thot I'd better ask here B4 becoming a candidate for a Darwin Award.
--Any useful advice appreciated!

Get a ceramic mortar and pestle from a gourmet cooking supply shop,
and do a match-head-sized lump at a time. Wear face protection and
gloves. Keep your supply and container for ground powder eight or ten
feet away, and keep dumping each little bit into the container.

I've done it when I couldn't get good primer powder for a flintlock
rifle. I've also ground up homemade powder this way, when I mixed it
wet and dried it into little lumps. I never had any drama from it.
Patience is better than drama.

--
Ed Huntress

Additionally , use a grounded strap on your wrist and all containers and
work surfaces . A static spark can kill you ! Wear cotton clothing - less
likely to build a static charge - and thin leather gloves for both
sensitivity and burn protection . BP is originally granulated while still
damp , with the exception of FFFFG , which is pulverized in a ball mill .
Every accident I've seen (only a few ,thankfully) involving HE and other
explosives/pyrothechnics has been caused by static discharge ... or sheer
stupidity , as in "hole ma beer an' watch this" .
--
Snag
"Still got ten , two , and two
For two years during the Viet Nam war I worked at the Cornhusker Army
Ammunition plant in Grand Island, Nebraska. One of the jobs on the
bomb making line was to take 50# boxes of TNT (sometimes Ammonium
Nitrate) off a conveyor line and unbox the sacks with the explosives
and dump them in a hopper where the contents dropped into huge wheeled
carts a floor below. Usually these bags were waxed paper. In addition
to all cotton clothes and special shoes and gloves we took all kinds
of precautions to prevent static electricity. One day two truckloads
of TNT cames in that were packed differently. They were wrapped in
plastic instead of the usual waxed paper. The station that unloaded
the first bag noticed a static electric spark when they emptied the
bag. Luckily no explosion! The lead man immediately hit the switch to
stop the conveyor line and called the foreman. The foreman called the
line supervisor and the safety man. The line supervisor we could keep
the bags in contact with the metal hopper while emptying and they
would not spark. The safety man was not going to say NO to the line
supervisor. However by this time the Union Steward had notified the
Union Headquarters about the problem and the Union honchos told her to
shut down the line. We all walked off because we knew it was dangerous
to continue unloading those plastic bags. Eleven million pounds of TNT
from that shipment was returned to DuPont to be repackaged. During a
follow up by the Union it was said that this 11 million pounds had
been rejected by another arsenal because of the spark hazard. Instead
of repacking then someone in the food chain decided to send it to us
because they thought our Union people would cave in. A perfect example
of just how stupid decisions are made by management all the time.

I tell anyone who will listen that unions are a necessary evil, then
quote why I think they are evil.

OK -- here's an example of why they are necessary.

--
Tim Wescott
Control system and signal processing consulting
www.wescottdesign.com