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Posted By : Charles Gramlich - 5/20/2008 10:02 PM
Here's my problem.  I know that gunpowder that is not contained will simply burn and not explode.  Putting gunpowder into a metal container, like with a pipe bomb, allows the pressure of the burning powder to build to the point of explosion before the metal ruptures.  I'm wondering if a more primitive society could create bombs of any decent strength by putting gunpowder inside a thick sewn-leather packet.  Anyone have any informed thoughts on the matter?


Charles Gramlich
 


Posted By : Greybeard - 5/20/2008 10:32 PM
A leather packet would likely just split along the seam, but a wooden barrel would explode satisfactorily.


Edwin


Posted By : Rob Mancebo - 5/21/2008 2:53 AM
Charles Gramlich said...
Here's my problem.  I know that gunpowder that is not contained will simply burn and not explode.  Putting gunpowder into a metal container, like with a pipe bomb, allows the pressure of the burning powder to build to the point of explosion before the metal ruptures.  I'm wondering if a more primitive society could create bombs of any decent strength by putting gunpowder inside a thick sewn-leather packet.  Anyone have any informed thoughts on the matter?

 
 
-  Okay, gunpowder 101 - 
 
-  'Black powder' (Which is what old-style saltpeter, charcoal, and sulpher powder is called now days) is an 'explosive'.  If you touch it off it explodes (dangerous stuff to monkey around with).  This translates to a fiery 'poof' even when not contained, and an explosion when contained. 
 
-  Modern 'smokeless powder' is a 'propellant'.  If it's touched off when un-contained it simply burns.  It sputters a little and can actually make a good flame, but burns like a road flare, not an explosion.  However, when contained, it causes pressures many times that of the old black powder. 
 
-  I've never heard of leather used to contain a black powder explosion.  Most early hand-bombs were pottery of some type.  The explosion only frightens and dazes the enemy, pottery shards are crippling.  So then, your leather bombs would work as a psychological weapon or on anyone within a foot or so of one (assuming they're using a substantial amount of powder)  They'd cause choking sulpher smoke, flame and noise.  Without some destructive material to project though, they wouldn't really kill anyone who's not right on top of them.  That's why the serrated pineapple casing around old WWII gernaides.  It would break up and toss shards of iron into everyone.  That's what does the damage, not the actual explosion.  (Although the explosion is demoralizing, deafening, and generally scary as the devil!)
 
 
 
 


Adventure-History-Fantasy-Folklore

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The Wastelander

Posted By : Anthony G Williams - 5/21/2008 2:55 AM
Some of the original hand grenades were clay pots with the opening sealed.
 
 


Tony Williams
Scales (2007), The Foresight War (2004)
Homepage: http://www.quarry.nildram.co.uk

SFF Blog: http://sciencefictionfantasy.blogspot.com/



Posted By : Charles Gramlich - 5/21/2008 3:01 AM
Thanks everyone for the input. I've seen black powder. I used to do a bit of muzzle loading hunting. I know how it will flare up when lit in an open space but how there is no explosion. I was figuring that the leather "bags" or satchels might be filled with nails. And that the bags would probably work best if banded with iron to help contain the pressure.


Charles Gramlich
 


Posted By : tchernabyelo - 5/21/2008 3:50 AM
The problem with leather is that it is likely to tear in one place and so the explosion will be directional (and without control). The iron banding might help, but if this primitive society can band iron around leather, they can make iron grenades anyway.

Is there a good reason not to use thin pottery filled with a mix of black powder and sharp scrap metal? The only real problem with those is their fragility in terms of transport.

I have a whole series of half-written novels that feature as a central plot point the introduction of black powder to a culture, and have spent some time considering the kind of experiments and uses that it might be put to. As it was "discovered" being used in mining in a foreign land, the first main thought is "if it can break rock, it can break walls" so it changes seige warfare, but once the secret begins to come out and the initial monopoly on it has gone, all sorts of fun ensues...


Brian Dolton
 
Land Of Wind And Ghosts stories:
"The Box Of Beautiful Things" - IGMS#3
"The Man Who Was Never Afraid" - Abyss and Apex #20
"At Blue Crane Falls" - Abyss and Apex #25
"Where No Wind Blows" - Staffs & Starships #2
"What The Sea Refuses" - Black Gate (forthcoming)
"What The Heart Bears" - Black Gate (forthcoming)
"Above The Clouds" - Paper Blossoms, Sharpened Steel (forthcoming)
"The Gray World" - Every Day Fiction (forthcoming)
"Three Out Of Four" - Sorcerous Signals Feb-Apr 08 
"The Dragon Path" - Fictitious Force #5
"The Last Arrow Of Liang Xi" - Darwin's Evolutions (forthcoming)
 
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"Call Centre" - Necrotic Tissue #1
"When Winter Came" - ASIM #32
"Cold Fire" - Flashing Swords #9
"St. Saviour And The Devil's Dandy" - Flashing Swords (forthcoming)
"In This City" - Fantasy Magazine (forthcoming)


Posted By : Rob Mancebo - 5/21/2008 4:03 AM
Charles Gramlich said...
Thanks everyone for the input. I've seen black powder. I used to do a bit of muzzle loading hunting. I know how it will flare up when lit in an open space but how there is no explosion. I was figuring that the leather "bags" or satchels might be filled with nails. And that the bags would probably work best if banded with iron to help contain the pressure.
 
-  That 'poof' BP makes when you ignite it is an un-contained explosion.  Stack some smallsticks close around a pile of about 30 grains of BP and see how many are still there after you touch it off.  The same expanding gas that scatters the sticks would go bang if it was contained. 
 
 
-  'Filled with' puts the nails in the center of the explosion not anywhere to be channelled outward.  Wrapped with nails would be better.  The explosion inside casts the outer shell of nails away to do damage.   
 
-  'Banding' leather with iron?  That's a lot of work to put expensive iron around a cheap leather sack.  Wood or pottery would be better, more destructive, and simpler.  Is there a reason you're set upon using leather?  As the author you can do what you want, but I don't see any benifit to leather. 


Adventure-History-Fantasy-Folklore

www.geocities.com/robmancebo/ 
The Wastelander

Posted By : Charles Gramlich - 5/23/2008 11:16 AM
Thanks again. I meant for the nails to be packed "around" the powder but just didn't say it right here. I've decided to use a combination of pots and wooden barrels for the bombs. The reason I was hoping to use leather was because I was going to have the good guys shoot some of the bombs (thrown by catapults) in midair with fire arros and have a kind of fireworks display. But I've solved that problem.

Thanks for all the input.


Charles Gramlich