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ecos
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Gun design
Hi All,
I have enough KClO3 and I was planning to shoot some metal balls. I am planning to use metal pipe like this one :
There will be a spring that will accelerate a nail to hit the EM and fire the ball.
Of course there nice explosion inside the metal tube (barrel) that will send the metal ball so far away like this pic (i know the picture has bullet
but i will do it with ball) :
My question here : what is the maximum amount of EM that I can use not to break the barrel ?
I think there will be a relation between the EM and the thickness of the barrel but I couldn't find enough info.
I read that AN was used before as gun powder but it shutters the guns after few 100 rounds since it is very strong. it sounds really critical to
choose the EM type and amount to have a proper gun.
ref of the pics : http://www.orions-hammer.com/blowback/
[Edited on 6-6-2016 by ecos]
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PHILOU Zrealone
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Depends on the EM, the mix...this is very risky/suicidal project!
I have used such pipe bombs with KClO3, S, C, CaCO3 and for some of my mixes even with 5 mm wall thickness, it was reduced to schrapnels of less than
1 cm²...
Chlorate mixes can be very brisant...I had a specific mix with an extremely fast burning rate that detonated from flame in a hard brass pipe (3cm
long, 3 cm diameter, 1 mm wall thickness) open on both sides put on the ground on one open end and filled with 2 thee spoons of light chlorate
powder...not pressed at all...with a 30 cm slow burning drinking straw fuse (10 sec delay)...it detonated...the brass was turned into copper dust!
Chlorate is for sure way too brisant for gun use...it burns too hot and is also very corrosive even to galvanized (Zn plated) iron pipe.
The screw on top caps will for sure be dangerous random projectiles with fast projection and rotation.
If by any chance it succeeds to shoot without being destroyed, the gun will be dirt by KCl or NaCl and rust, maybe deformed or structurally
weakened...causing troubles for further attempts...
[Edited on 6-6-2016 by PHILOU Zrealone]
PH Z (PHILOU Zrealone)
"Physic is all what never works; Chemistry is all what stinks and explodes!"-"Life that deadly disease, sexually transmitted."(W.Allen)
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ficolas
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Can you stimate the pressure and the temperature of the barrel when the EM explodes? If so maybe using T = PR/t, where T is the tension, p the
pressure, R the radius and t the thickness, and comparing the values with a table like this one http://www.engineeringtoolbox.com/stainless-steel-pipes-pres... for your material and temperature?
This is probably a wrong route thought.
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careysub
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You don't know what you are doing. Do not attempt this project, as described.
If you want to launch projectiles use commercial black powder or make the equivalent (lots of stuff on making black powder), and then study interior
ballistics to learn the relationships between propellant loading density and chamber pressure.
Propellant powders were designed to do this with predictable, useful burn rates and pressure curves, and decades of experimentation went in to
perfecting them.
Edit: I took out the suggestion to look at smokeless powder, I agree that even that is risky for someone not skilled in gun smithing.
[Edited on 7-6-2016 by careysub]
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OneEyedPyro
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I would suggest only black powder for a project like this, even smokeless powder is too risky since slight variations in charge weight can have a
significant influence on peak pressure. Chlorate mixtures sound like a very bad idea to me.
If you must do this be sure to start with small amounts of BP and work up in small increments.
I'd suggest doing some remote testing as well.
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NeonPulse
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Surprisingly this thread has not been locked yet. It's a rather dangerous idea. Perhaps a simple cannon fuelled with a quality black powder would be a
much safer alternative if all you want to do is fire some bearings.
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careysub
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Quote: Originally posted by NeonPulse  | | Surprisingly this thread has not been locked yet. It's a rather dangerous idea. Perhaps a simple cannon fuelled with a quality black powder would be a
much safer alternative if all you want to do is fire some bearings. |
But it is good that people come here to propose projects, and thus get potentially life-saving safety advice.
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ganger631
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Really ambitious project and seems rather dangerous,however i was wondering how are you going to rifle the barrel?
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Bert
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I concur that chlorate is NOT a good candidate for the oxidizer in an amateur gun propellant, especially in an improvised "zip gun" of unspecified
metallurgy/design parameters!
If you absolutely MUST home build an improvised gun, black powder is your best choice.
ecos, I do believe your user name has RATHER comprehensively navigated the circuit of historically common propellant options here on the board, asking
questions on both their rocketry and gun applications- You did learn something from doing that?!
Every classical muzzle loader era attempt to use chlorate in black powder analogue propellants led to a dramatic failure, and usually came to a sticky
end, sometimes including deaths of the associated powder mill workers (see Berthelot and the Essone stamp powder mill). The armies of Europe, the
Americas and much of Asia played with this chemistry and related engineering before single, double and triple based smokeless powders were accepted
as 20th century state ok for the art. And, all abandoned the effort after finding the increase in performance not worth the increase in sensitivity
and related dangers associated with storage, manufacture and handling of industrial quantities of such propellants.
Please do not piss on the electric fence yourself in order to confirm two centuries of failure to safely and effectively implement such.
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Text
Explosives and Their Power.
Translated and Condensed From the French of M. BERTHELOT
By C Napier Hake and William Macnab
London: John Murray 1892
( 518 )
CHAPTER XI.
POWDERS WITH CHLORATE BASE.
§ 1. GENERAL NOTIONS.
1. BERTHOLLET, after having discovered potassium chlorate, and
recognized the oxidizing properties so characteristic of this salt,
thought of utilizing it in the manufacture of service powders. He
made several attempts in this direction, but immediately suspended
them after an explosion which happened during the manufacture
carried on at the Essonnes powder factory, an explosion in which
several persons were killed around himself. The same attempt has
been revived at various periods, with certain variations in the
composition.
But in every case explosions, followed by loss of lives-such, for
instance, its those which happened during the siege or Paris in
1870, and at L’ Ecole de Pyrotechie in 1877-- happened before
long in the course of its manufacture.
it is thus clear that potassium chlorate is an extremely dangerous
substance, which is only natural, because its mixture with
combustible bodies is sensitive to the least shock or friction. The
catastrophe in the Rue Beranger (see p. 46), produced by an
accumulation of caps for children's playthings, [Armstongs Mixture
djh] containing potassium chlorate, has helped to confirm these
ideas. Chlorate powders are, generally speaking more easily
ignited, and burn with more vivacity than black powder. They
explode, like the latter, on contact with an ignited body. They are
hardly used at the present day, [<1892! djh] except as fuses for
fireworks, or to produce shattering effects in torpedoes, for
instance. A powder of this kind has even been proposed in America
as motive agent of forge-hammers or pile-drivers. In this case the
cartridge is placed between the head of the pile and the ram, when
the explosion drives in the one and sends the other upwards. Their
strength is superior to that of nitrate base powders, but less than
that of dynamite or gun-cotton.
2. We shall first state the general properties of chlorated
compositions. Potassium, chlorate, which is the essential
ingredient, is a salt fusible at 334, and which decomposes regularly
at 352'. Nevertheless, it may become explosive by itself under the
influence of a sudden heating, or a very violent shock (p. 406).
We have seen that it yields 39-1 per cent. of oxygen and 60-9 of
chloride of potassium—
ClO3K = KCl + 03,
liberating, at the ordinary temperature, 11 Cal. for each equivalent
of oxygen (8 grms.) fixed; or 1.4 Cal., per gramme of oxygen; or
0-54 Cal. per gramme of potassium chlorate.
These quantities of heat must therefore, generally speaking, be
added to those which would be produced by free oxygen, when
developing the same reaction at the expense of a combustible
body (p. 134). But the presence of the potassium chloride, which
acts as inert matter, tends to lessen this advantage.
3. The extreme facility with which potassium chlorate powders
explode under the influence of the least shock is a consequence of
the great quantity of heat liberated by the combustion of the
particles which are ignited at the very outset and their low specific
heat; this heat raises the temperature of the neighbouring portions
higher in the case of chlorate than of nitrate powder, and it
therefore more easily propagates the reaction. The influence is the
more marked the lower the specific heat of the compounds, [1] and
as the reaction commences, according to the known facts, at a
lower temperature with the chlorate than with) the nitrate of
potassium.
Everything, therefore, combines to render the inflammation of the
powder with chlorate base easier.
Therefore the substances of which they are formed should not be
pulverised. or crushed together, but pulverized separately and
mixed by screening.
The drying in the stove of these powders is dangerous. The
presence of powdered camphor, so efficacious with gun-cotton,
does not lessen the sensitiveness of chlorate powders.
4. Not, only is the chlorate powder more energetic and
inflammable, but its effects are more rapid; it is a shattering
powder. Theory again is able to account for the property. In fact,
the compounds formed by the combustion of chlorate powder are
all binary compounds, the simplest and most stable of all, such as
potassium chloride, carbonic oxide, and sulphurous acid. Such
compounds will undergo dissociation at a higher temperature and
in a less marked manner than the more complex and advanced
combinations, such as potassium sulphate and carbonate, or
carbonic acid, which are produced by nitrate powder. It is for this
reason that the pressures developed in the first instance will be
nearer the theoretical pressures with chlorate than with nitrate
powder, and the variation in the pressures produced during the
expansion of the gases will be more abrupt, being less checked by
the action of the combinations successively reproduced during the
cooling.
5. The explanations just given apply not only to powders in which
potassium chlorate is mixed with charcoal and sulphur, compared
with analogous powders with nitre as base, but also comprise all
powders formed by the association of the same salts with other
substances. It can be shown that this is so, without entering into
special calculations, for which the exact values would in the
majority of cases be wanting.
Now, our comparisons are based on the following data, which
present a general character: —
1st. Both salts employed in equal weights supply to the bodies
which they oxidise the same quantity of' oxygen. 122-6 grins. of
chlorate yield 6 equiv. or 41 grins. of oxygen; that is to say, 8 grins.
of oxygen for 20 grins. of chlorate; whilst 101 grins. of potassium
nitrate yield only 5 equiv., or 40 grins. of available oxygen, viz. 8
grins. of oxygen to 20-2 grins. of salt. Hence it follows that both
salts must be employed in equal weights in the greater number of
cases.
Now, one and the same weight of oxygen, 8 grams., yielded by
potassium chlorate liberates + 11 Cal. more than free oxygen; if it
be yielded by the nitrate, it produces 19.3 Cal., or 6.95 Cal. per
gramme of Salt employed.
The formation of the same compounds will therefore liberate more
heat with the chlorate than with the nitrate, and the excess will
subsist, even in taking into account the union of the acids of
sulphur and carbon with the potash of the nitrate.
This greater quantity of heat will give rise to a higher temperature,
since the mean specific heat of the products is less with the
chlorate than the nitrate. The mean specific heat of the products at
constant volume may be calculated theoretically by multiplying the
number of atoms by 2-4, and dividing the product by the
corresponding weight. Now, the weight of the combustible body
being the same will require the same respective weights of nitrate
and chlorate, according to what has just been said; but the latter
will correspond to a less number of atoms, since the equivalent of
chlorine is greater than that of nitrogen.
2nd. The volume of the permanent gases is greater, or at the
lowest equal, with potassium chlorate than with the nitrate,
because the potassium of the former salt remains in the form of
chloride, the whole of the oxygen acting on the sulphur and carbon
to produce gases; whereas the potassium of the nitrate retains a
part of the oxygen, at the same time as it brings. a portion of the
sulphur and carbon to the state of saline and fixed compounds, the
formation of the salts more than compensating, for the volume of
nitrogen set free.
3rd. In the case where only the carbon or 6, hydrocarbon burns, the
compensation in the gaseous volumes is exactly effected because
each volume of nitrogen liberated from the nitrate replaces an
equal volume of carbonic acid combined with the potassium yielded
by the said nitrate. Nevertheless the pressure will be increased,
even in this case, with the chlorate, because its temperature is
higher.
4th. The compounds formed with the chlorate being in general
simpler than with the nitrate, dissociation will be less marked, and
consequently the action of the pressures will be at once more
extended, because the initial pressure is greater, and more abrupt,
because the state of combination of the elements varies between
narrower limits. Hence arise shattering effects rather than those of
dislocation or projection.
6. Potassium chlorate possesses another property which has
sometimes been utilized. Its mixture with organic substances, or
with sulphur or other combustible bodies, takes fire under the
influence of a few drops of concentrated sulphuric acid ; which is
due to the formation of chloric acid, which is immediately
decomposed into hypochloric acid, an extremely explosive
compound and a very powerful combustive.
This property has been utilized to cause the ignition by shock of
torpedoes and hollow projectiles charged with potassium chlorate
powder. It is sufficient to place in them a tube or glass balls, filled
with concentrated sulphuric acid.
This artifice may even be employed to ignite chlorate fuses for
exploding dynamite or gun-cotton.
But all these arrangements are very dangerous for those who put
them into execution, and they have not been practically adopted.
7. We have yet to say a few words about potassium perchlorate,
which is generally regarded as equivalent to the chlorate, but by a
mere theoretical generalization, for it is a salt which is expensive,
difficult to prepare pure, and it has hardly formed the object of real
experiments as an explosive agent.
Weight for weight it yields a little more oxygen than the chlorate;
about a sixth, viz. 46.2 per cent instead of 39.1.
ClO4 = KCl + 04,
But this liberation of oxygen absorbs heat; - 7.5 Cal. per equivalent
of salt, or - 0.9 Cal. per equivalent of oxygen, instead of liberating
it.
From this point of view, therefore, the perchlorate acts almost like
free oxygen, with the disadvantage of half of it being useless inert
matter.
Pure perchlorate is not explosive either by shock or inflammation,
as the chlorate. Further, its mixtures with organic substances are
far less sensitive to shock, friction, the action of acids, etc. They
ignite with more difficulty and burn slower.
[1] The fact, these two powders only differ by the substitution of the
chlorate, the specific beat of which is 0.209, for the nitrate, the
specific heat of which is 0.239.
[2] Supposing it to act upon a carbonated body, the carbon of
which is changed into potassium carbonate.
--
donald j haarmann
----------------------------
A man would create another man if one did not
already exist, but a woman might live an enternity
without even thinking of reproducing her own sex.
Johann Volfgang Goethe
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Rapopart’s Rules for critical commentary:
1. Attempt to re-express your target’s position so clearly, vividly and fairly that your target says: “Thanks, I wish I’d thought of putting it
that way.”
2. List any points of agreement (especially if they are not matters of general or widespread agreement).
3. Mention anything you have learned from your target.
4. Only then are you permitted to say so much as a word of rebuttal or criticism.
Anatol Rapoport was a Russian-born American mathematical psychologist (1911-2007).
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macckone
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There were actually chlorate gun powders used in the past. They were found to be too corrosive. As with any mix, it is possible to regulate the burn
rate with additives. Because they did it over a century ago, we know it can be done. However, this is not a beginners project. If you don't have an
EM test range then you should not be doing this. If you can't fire from 50 yards away with a concrete wall between you and the device then you
shouldn't do a project like this.
Chlorate powder patent:
http://www.google.com/patents/US765999
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ecos
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Thanks all for the info. I really appreciate it.
I am convinced now that chlorate is a bad option for guns.
I will try to use ammonium nitrate since it is easier to find (fertilizer) or I will make BP.
the missing information , what is the relation between the barrel thickness and the amount of BP?
logical wise the thicker is the better but at least there shall minimum thickness to the barrel.
[Edited on 8-6-2016 by ecos]
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NedsHead
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Must everything be acronyms? oh..sorry, MEBA.
What is this BB?
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careysub
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I think he means BP.
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ecos
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sorry for the mistake, I fixed it.
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chemrox
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I wouldn't use plumbers pipe for a gun barrel. If you want to pursue home-made guns, a laudable enterprise IMHO, get one of those small lathes made
for hobbyists and acquire some gun metal stock. You could also retrieve some gun barrels from a dealer that tears down firearms. You can buy barrels
through SHOTGUN NEWS and other like pubs. I share concerns about chlorate powders. Zn/S mixes work and aren't nearly so unstable when freshly mixed.
"When you let the dumbasses vote you end up with populism followed by autocracy and getting back is a bitch." Plato (sort of)
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unionised
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| Quote: Originally posted by ecos | Hi All,
I have enough KClO3 and I was planning to shoot some metal balls. I am planning to use metal pipe like this one :
[Edited on 6-6-2016 by ecos] |
I agree with the people who have said "don't do this".
If you persist in doing it anyway- write your will first, and make sure there's someone round the corner to call the emergency services for you. (It's
difficult to dial 911 without eyes or fingers)
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ecos
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@chemrox, what is "laudable enterprise IMHO" ?
@unionsid, please check my last comment.
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Twospoons
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| Quote: Originally posted by ecos |
the missing information , what is the relation between the barrel thickness and the amount of BP?
[Edited on 8-6-2016 by ecos] |
This question worries me. It tells me you do not have sufficient knowledge of engineering to attempt this project safely. If you still want to fire
things I'd suggest you use cardboard tubes and projectiles - just a little safer if things go wrong. Figure out a remote trigger that keeps you well
clear of the action. I used to use a neon sign transformer on a long lead to ignite BP in a cardboard "cannon".
Once you finish your mech. eng. degree, then try building a metal gun.
Helicopter: "helico" -> spiral, "pter" -> with wings
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gregxy
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You can buy replica black powder guns, they are legal and they are not considered firearms under federal law. Making a zip-gun like this is not
legal, even if it is a much greater danger to you than anyone else.
If you do this, use black powder like the others have said and use a volume of powder less than the volume of the ball bearing.
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OneEyedPyro
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| Quote: Originally posted by gregxy | You can buy replica black powder guns, they are legal and they are not considered firearms under federal law. Making a zip-gun like this is not
legal, even if it is a much greater danger to you than anyone else.
If you do this, use black powder like the others have said and use a volume of powder less than the volume of the ball bearing.
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Depending on where he lives it may be perfectly legal, in the US you can build your own guns so long as they are the proper dimensions (for
smoothbores it must be at least 28 inches in overall length with an 18 inch barrel).
IMO the actual risk of severe injury is quite low assuming a the pipe and breechface are sufficiently thick.
I think some safety glasses and welding gloves would pretty well mitigate most of the serious bodily damage with a reasonable charge of BP 
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ecos
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All thinks that I am going to risk my life.
I try things from remote distance.
you made me give up the whole project  !!!
@Twospoons
| Quote: |
This question worries me. It tells me you do not have sufficient knowledge of engineering to attempt this project safely. |
Just a reply to your comment, I have a higher engineering degree than you can imagine.
This a professional question but you didn't get it!
[Edited on 10-6-2016 by ecos]
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hissingnoise
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| Quote: | | This a professional question but you didn't get it! |
What the...!
How fucking ironic is that?
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Maker
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| Quote: |
Just a reply to your comment, I have a higher engineering degree than you can imagine.
This a professional question but you didn't get it!
[Edited on 10-6-2016 by ecos] |
I'm pretty sure we can all imagine higher level degrees than are possible to obtain, so please, don't be so cocky. If you had a high enough relevant
qualification then you wouldn't need to ask
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aga
Forum Drunkard
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I have no degrees, well, maybe of burn at times.
Even us lowly uneducated scum find the whole notion laughable:-
OP wants to make a Gun, is super-educated in engineering/mechanics and still wishes to use off-the-shelf plumbing/electrical pipe with an unknown
propellant. LMAO.
Even a dullard like me would want to know :-
Expansion rate of the propellant
Diameter/length/weigh of projectile
Projectile material properties
... before finding the equations that certainly exist to calculate the pressures/fricative forces to find out how 'strong' the barrel material has to
be etc etc.
Unresearched speculation (and suggestions) on ghetto Gun Design is definitely over The Line IMHO.
What's next ?
"Best suggestions for max impact IED deployment tactics in downtown Washington ?"
Lockdown time - too much good stuff in reponse to the OP to qualify for Detritus.
[Edited on 10-6-2016 by aga]
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nitro-genes
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Brass balls are admirable, but as endcaps on a gun not so much... Most metal
piping is welded btw and not seamless, can't tell for sure from the photo, but it looks like ordinary plumbing pipe which is probably welded. This
thing wouldn't survive blackpowder, let alone a chlorate based propellant...Even if it would survive a couple of blackpowder shots, the material will
fracture (as it wasn't meant for this) and may suddenly give in while you are holding it. Recipe for getting seriously hurt.
[Edited on 10-6-2016 by nitro-genes]
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