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ecos
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Quote: Originally posted by nitro-genes | 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] |
I just added a photo for a zip gun from internet. I was planning to use water pipes instead since they are thicker.
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ecos
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I found a lot of books on internet about how to make a gun : http://www.prexis.com/sten/Holmes_50.pdf
this book is for 50 cal gun.
I have no interest in following the schematics , I am behind the science of how it was designed and different aspects.
[Edited on 10-6-2016 by ecos]
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Tsjerk
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You really don't get it do you? You cannot use any welded tubing for the barrel. It is just not going to work.
Besides that, do you have any idea about the kind of steal (assuming you are going for steal) your water pipes are made of? And with kind I don't mean
iron....
Long story short: any amount of black powder between two metal balls in a metal water pipe makes a nice pipe bomb. If this is not the case I'm sure
you are not going to be satisfied with the monding speed and you are going to crank it up until you do have pipe bomb.
Edit: and yes, water pipes are welded
[Edited on 10-6-2016 by Tsjerk]
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nitro-genes
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Make sure you also read "How to build an Abrams tank from plumbing supplies" by Prof. Dr. Dick Head...
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ecos
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, the gun was made by many people on youtube.
if you are interested , I can share links.
@Tsjerk, Thx for the info.
[Edited on 11-6-2016 by ecos]
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morganbw
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Good God people. Let the man make his gun. Smart (maybe not ) but he will discover quickly enough if it works or not. For me I would simply buy one,
but I am not he.
I do agree that black powder should be considered.
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aga
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https://www.youtube.com/watch?v=QM7kCcfdcsE
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ecos
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simple zip gun in action : https://youtu.be/KRSxf87WfLw
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doomeister
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If you are going to build a firearm, please use black powder. If you are hellbent on using smokeless, please don't use plumbing pipe. Try to look for
some seamless steel barrels, 4140 or 4150 chrome moly, or if must be, some BSP piping.
Strong men bring Good times,
Good times make Weak men,
Weak men bring Bad times,
Bad times build Strong men.
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ecos
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Thx for the warning.
I have a question , the BP inside the bullet undergoes deflagration or detonation?
i think designing a gun is more complex than I thought : https://www.youtube.com/watch?v=1rPm-9ujt0Y
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Metacelsus
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Deflagration. Detonation would destroy the gun (and possibly maim the wielder).
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careysub
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Quote: Originally posted by ecos | Thx for the warning.
I have a question , the BP inside the bullet undergoes deflagration or detonation?
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Deflagration. One reason that BP is strongly recommended as a propellant is that it cannot detonate.
Yes it is. I suggested consulting a book on interior ballistics for a reason.
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ecos
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@careysub do you have a book to recommend?
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NedsHead
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My advice is to start out with straight wall black powder pistol calibres and stay away from bottleneck cartridges until you have some experience, I'm
starting a project of my own soon, I'll let you know how it goes
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ecos
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@Nedshead, looking forward for your result Good luck.
I forgot to mention my reference and video for the book which explains how to make a 50 cal gun.
book : www.prexis.com/sten/Holmes_50.pdf
step by step video : https://youtu.be/KQe8gVxxsyk
I must admit that i got surprised when I knew that BP deflagrate not detonate. I thought the bang sound is due to small explosion that gives kinetic
energy to bullet to move fast.
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PHILOU Zrealone
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Deflagration can go over the 350 m/s (speed of sound in air) up to >2000 m/s
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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hissingnoise
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This thread has made me uneasy at its outset and I'm quite surprised and somewhat dismayed that Polverone has allowed this thread continue, especially
in light of recent events, one of which featured a homemade gun used in committing a coldblooded murder!
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PHILOU Zrealone
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Quote: Originally posted by hissingnoise | This thread has made me uneasy at its outset and I'm quite surprised and somewhat dismayed that Polverone has allowed this thread continue, especially
in light of recent events, one of which featured a homemade gun used in committing a coldblooded murder!
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Give a knife to a fanatic idiot and he will do a disaster...as bad if not worst as with a gun...
With the minimum chemical knowledge a fool can do a mass killing... (fire, gas explosion, chemical weapons)
A one shot gun is really the least problem...the problem is the shooter and his insane mind...
[Edited on 20-6-2016 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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OneEyedPyro
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Quote: Originally posted by hissingnoise | This thread has made me uneasy at its outset and I'm quite surprised and somewhat dismayed that Polverone has allowed this thread continue, especially
in light of recent events, one of which featured a homemade gun used in committing a coldblooded murder!
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Considering all of the attacks with explosives over the years they might as well close the entire energetics section, it's that type of attitude that
gets common chemicals like acetone and H₂O₂ banned.
Blame the fool not the tool!
[Edited on 20-6-2016 by OneEyedPyro]
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nitro-genes
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In general I agree to the statements above regarding closing this discussion, due to the missing science, novelty, and mainly practical discussion
about something that could be seen as a weapon. (Hey guys, look...I'm gonna build .50 canon from youtube) Then again, like said before, it's all about
the person, in principal everything can be used as a weapon, though sciencemadness is not the place IMO to discuss these things. Like the E&W
forum, it also tends to attract another type of crowd so to say. Besides, sciencemadness also isn't the best forum for this probably, as there are
likely other more specific fora on the internet with more knowledgeable people regarding this subject, which would mainly involve machining skills and
knowledge about specific alloys and their properties and much less about energetic materials.
Some things to keep in mind though:
Point 1: In many countries weapons are in fact legal, sometimes even without any special license. It's pretty small minded to think of one particular
incident, involving a particular firearm, in one particular country, having a particular law regarding firearms, to consider not allowing any
discussion regarding this matter.
Point 2: This board is called Sciencemadness for a reason, one could argue there isn't much science in propelling things from a barrel (there actually
is, just not in this thread.) On the other hand sometimes it's a bit of a grey area, for example, a light-gas gun would be very similar, though
discussion would likely be allowed due to science interest and non-weapon use. And lets not fool each other in thinking that experimenting with
energetic materials is much more dangerous than other types of chemistry. I'd rather have someone experimenting with making a blackpowder rifle from
scratch than one mass producing ketene for acetic anhydride or working with large amounts of ether as my neighbour. Many potentially misusable and
dangerous chemicals and potential precursors are openly discussed here, same goes for bacterial strain isolation and growth media, which is a real
potential threat taken very seriously nowadays and implemented as part of safety and regulation prescriptions in many biochemitry labs. We should also
not discuss making of alkaline earth metals, these are very explosive when in contact with ordinary water!
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ecos
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I am not talking about mechanical designs , machinary tools , ...etc
I am talking about using EM for making a rifle. In the beginning of the thread I was talking about AP as gun powder.
The forum here discuss a lot about EM as explosives. this can make a disaster.
A gun or a bullet is less problem than this.
2000 m/s sounds like a detonation not a deflagration !!
wouldn't a small controlled detonation give more power to the bullet and require less EM ?
[Edited on 21-6-2016 by ecos]
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OneEyedPyro
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A detonation is just far too powerful, if using high explosives was a feasible method for launching projectiles they would already be doing it. No
offense but if you're actually considering using an HE in a gun you are obviously pretty clueless about all of this.
What gives a bullet power is not the peak initial pressure but rather the average pressure through the entire length of the barrel.
Peak pressure is however what will blow up a gun.
A 9MM has about 35,000 PSI which is considered fairly high pressure for a pistol round, even a relatively weak HE can produce millions of PSI upon
detonation.
[Edited on 21-6-2016 by OneEyedPyro]
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nitro-genes
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Regarding the propellant, I actually think there are many more possibilities than blackpowder or nitrocellulose. The problem is that the amount of
pressure produced in the barrel of a binary fuel/oxidizer mix depends on many factors, for example type of oxidizer and fuel, oxygen balance, particle
size, density, type of initiation, cardridge shape, powder load and cardridge diameter, projectile weight and projectile material etc. Even something
relatively tame as blackpower comes in differnt grades, the fastest revolver grades loaded in a canon would likely destroy it was well. For
nitrocellulose, a great deal of reserach has been performed to determine all of these factors to come to a reliable propellant, as the material is a
high explosive in it's own right and can be detonated under the right circumstances. For many possible propellants out there, these things have not
been determined thoroughly as they have never been used commercially, while some like ammonpulver have been used succesfully. Apart from the
instability, sensitivity and chloride induced barrel erosion of propellants using chlorates, it would be possible to actualy use it as a small arms
gunpowder, by careful consideration of all factors involved. For example considerable overfueling of the chlorate mix will likely bring barrel
pressures down, so do smaller loads and possibly particle sizes. If one would be to experiment with this though, this would be just that, an
experimental setup, treated as if it is a pipebomb, never to be trusted for actual use. Certainly not with welded plumbing pipe made of low grades of
steel.
I would actually find it interesting if someone would build a decent standardized setup and measure projectile speeds with unconventional binary or
mono propellants. For example, those containing a combination of combustible gasses and an inert light gas, like helium or excess hydrogen. Maybe a
solid binary or even monopropellant may be possible, releasing much hydrogen gas upon deflageration, increasing bullet speed. Seeing some of these
high nitrogen/hydrgen heterocycle EM's I've been wondering if something like that could be advantagous in producing higher projectile speeds with
virually no barrel errosion. Nano aluminium coudl also help here, although would likely result in more errosion. Cost would be much higher than normal
NC though...
[Edited on 21-6-2016 by nitro-genes]
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PHILOU Zrealone
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Quote: Originally posted by ecos | In the beginning of the thread I was talking about AP as gun powder.
2000 m/s sounds like a detonation not a deflagration !!
wouldn't a small controlled detonation give more power to the bullet and require less EM ?
[Edited on 21-6-2016 by ecos] |
1°) "In the beginning of the thread I was talking about AP as gun powder."
Not AP (Ammonium perchlorate) but AN (ammonium nitrate) and KClO3!
2°) Deflagration is when the burning speed of the flame front is less than the speed of sound from the front flame shock wave(into the
material) if both are equal then it is a detonation.
The speed of sound in air at stp is approx 350 m/s, but in liquids like water or in solids like metals, crystals...the speed can go to several km/s.
So 2000 m/s is not per se a detonation.
The speed of sound is also dependant from the heat and pressure of the material...
A space shuttle or some planes do propel themselves at speeds like Mach 7 (7* the speed of sound in air = 2450 m/s)
And those are not detonating!
3°) You are speaking of EFP (explosive formed projectiles) if you plan to use detonating EM to propel a bullet...your bullet wont be a bullet
anymore, it will display totally different dynamic because it will become plastic deformed by the heat-pressure and by the air friction...making it
look like wet clay, playdoh, honey or water as a function of its cohesion, hardness and elasticity.
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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Hennig Brand
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I have built a couple guns over the years just for experimental purposes. If I was to build another I think I would use hydraulic piston tubing/pipe,
as it comes in a variety of diameters and wall thicknesses, it is seamless, made to handle high pressure and made of quality materials (in general).
Black power works, is reliable and reasonably safe, however, the extreme performance increase, relatively little fouling, etc, that comes with
smokeless propellants makes them worth the extra effort in my opinion. Keep in mind it is a lot of extra effort and even after hundreds of hours I
never made it all the way, but I know fairly well what needs to be done.
It is important to try new things, without some risk very little is gained, however, a careful risk assessment should be performed and if proceeding
reduction of as many hazzards as possible should be basic practice.
[Edited on 22-6-2016 by Hennig Brand]
"A risk-free world is a very dull world, one from which we are apt to learn little of consequence." -Geerat Vermeij
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