Sciencemadness Discussion Board - Nipolite and gunpowder + PETN (replacing gunpowder)

Nipolite and gunpowder + PETN (replacing gunpowder)

KINTF - 4-12-2011 at 23:07

I've read that germans used special gunpowder(nitrocellulose) in their aircraft machine guns that was a composition of PETN, stabilizer and an ordinary smokeless powder in rations of 64.7:1.3:34. It is said that this composition yielded a lot more powerful charge but which did not increase the actual discharge pressure. They also reported that there was merely no visible muzzle blast, which was good in dark conditions, nor a little smoke produced.

I was thinking of testing out this composition one day, since gunpowder is so expensive and rather scarcely available in where I live - and of course, if this works, it would increase the efficiency of the cartridge.

Does anyone have heard of this type of experiments or even tested them by themselves? I find this very interesting topic.

I would also be very interested in discussing wether it would actually be possible to replace completely the current smokeless gunpower and the priming cap with some other energetic material or materials that could be DIY.

[Edited on 6-12-2011 by KINTF]

hissingnoise - 5-12-2011 at 03:50

Quote:

I was thinking of testing out this composition one day, since gunpowder is so expensive and rather scarcely available in where I live - and of course, if this works, it would increase the efficiency of the cartridge.

The powder you describe, though quite powerful, would be very erosive and would not be flashless!
Aircraft-mounted guns, generally, do not require a flashless propellant . . .

VladimirLem - 5-12-2011 at 08:54

interesting stuff...especially because pure PETN burns very slowly...so if im gonna substitute PETN with MHN i got a really strong and good working propellant, right?

im searcing for some good propellant for an project (going to post it here if sucessful)

KINTF - 5-12-2011 at 22:45

The other actual point of this topic would be to discuss, wether it'd be possible to completely replace the ordinary nitrocellulose gunpowder composed with single or multiple energetic substance. Also the priming composition should be looked upon for not to cause detonation, but just to initiate deflagration - casting ETN/HMTD/fulminate into priming cap would cause case-full of PETN/MHN/XXX - substance to go full detonation, blasting up the gun.

Black powder is not suitable since it will foul modern guns and it is not powerful enough.

VladimirLem - 6-12-2011 at 07:12

Quote: Originally posted by KINTF

The other actual point of this topic would be to discuss, wether it'd be possible to completely replace the ordinary nitrocellulose gunpowder composed with single or multiple energetic substance. Also the priming composition should be looked upon for not to cause detonation, but just to initiate deflagration - casting ETN/HMTD/fulminate into priming cap would cause case-full of PETN/MHN/XXX - substance to go full detonation, blasting up the gun.

Black powder is not suitable since it will foul modern guns and it is not powerful enough.

yeah, thats right...nitrocellose is really "expensive" stuff compared to ETN or others...

Fast burning/easy to ignite (60-70%)
HMTD/APEX

NC
nitrostarch

solwly burning (30-40%)
MHN/ETN/PETN

I would go for Nitrostarch und MHN

KINTF - 11-12-2011 at 12:08

Well, as far as I can obtain sulfuric acid, nitric acid up to 1 eur per kg and penta up to 5 eur per kg, it is at least 20-fold cheaper from my point of view. Nitrocellulose powders cost of 50 euros per kg minimum at here, and being under strict licensing makes obtaining very hard even if somebody happens to have some spare cash.

quicksilver - 11-12-2011 at 14:04

Quote: Originally posted by KINTF

I've read that germans used special gunpowder(nitrocellulose) in their aircraft machine guns that was a composition of PETN, stabilizer and an ordinary smokeless powder in rations of 64.7:1.3:34. It is said that this composition yielded a lot more powerful charge but which did not increase the actual discharge pressure. They also reported that there was merely no visible muzzle blast, which was good in dark conditions, nor a little smoke produced.

I was thinking of testing out this composition one day, since gunpowder is so expensive and rather scarcely available in where I live - and of course, if this works, it would increase the efficiency of the cartridge.

Does anyone have heard of this type of experiments or even tested them by themselves? I find this very interesting topic.

I would also be very interested in discussing wether it would actually be possible to replace completely the current smokeless gunpower and the priming cap with some other energetic material or materials that could be DIY.

[Edited on 6-12-2011 by KINTF]

Please post source.

Triple Based Smokeless Powder (TBSP) does exist (please see Brassey's collective work on Explosives, Propellants: Vol. II - 1989) but in very well researched scenarios & are a relatively new phenomenon.
TBSP was typically mfg with nitroguanadine, which is a COOL burning material.
German mfg of PETN utilized a precursor known as "pentaerythritol-M" (not the materials utilized in vinyl & paint mfg.) This was [and still is], a very expensive material and one of the reasons why RDX is utilized much more than PETN in the first place. There is a lower nitrated material known as PEN: which is the TRINITRATE. This is common when lower quality precursor is utilized(Rhom & Has Company, Apache Powder / DuPont, USA).
The concept of PETN being a "hot burning" material is correct in-so-far as the very complex development methods used to alter an explosive to a propellant.
TBSP's are used most often in 20mm cannon and larger. The requirement for a cool propellant is vital in thinner walled barreled assemblies.
If the point is that alternative propellants were used during WWII - it is also important to understand that the war-time use of newer, higher brisant, VoD explosives was in very great demand even in the USA (which as many remember TNT supplies were stretched; via Ammatol with ammonium nitrate). Using an expensive precursor material was simply not in the cards. The depth of research needed to alter new explosives to be used as propellants was much greater than the route of a cooling system for conventional materials during that period in history.

On average for a well funded company such as Allient or Hogden to bring a new powder to market generally requires years of research prior to public or military usage.

KINTF - 19-12-2011 at 15:45

Ok,

Could the smokeless gunpowder used for modern, self-loading weapons that contain cavities (gas pistons, etc) that could get stuck with some solid residue, be made out of something you could offer from this board? Are chlorates mixed with something a good choice or not?

grndpndr - 19-12-2011 at 18:59

Please dont get the notion your going to manufacture/utilize some homemade propellant for a modern firearm and come away unscathed.If you presume to make a sort of NC/NG-EGDN,ETN etc propellant your more than likely to make a bomb.
Modern smokeless propellants come in dozens if not hundreds of variations for different applications and in fact even using factory components if thier not chosen/assembled correctly
you will again have a bomb.I took a(deceased) friend to hospital after a 'minor' incident involving reloading.He wasnt the sort who should have been reloading to begin with, never read instructions and neglected? to zero his powder scale.Result?A few grains to many of his chosen propellant blew the extractor out of the pistol's slide dismantled the magazine while it was blown out of the bottom of the pistol(hes lucky the cartridges in the magazine didnt deflagrate in an explosive manner).Not a POS Raven arms pot metal gun but a high quality civilian model of the militarys 9x19mm Beretta M9.He was lucky to get away with JUST metal fragments/high pressure gas blown into his eyes.He was in fact lucky and did regain his eyesight.

If you do decide to make your own propellant please take this bit of advice and secure your weapon(one you arent emotionally-$ attached to) to a tire if its a longun and pull the trigger with a string from a good distance away.Likewise with a pistol-etc. same idea .Think about it!!

PS; chlorates will rust shit out of those nooks and crannies
you describe in a gas operated wpn(even chrome lined military wpns arent immune) nescessitating a thorough cleaning with plain water or a water based cleaner.
In addition a black powder type of propellant wont produde the needed pressure in a self loading wpn besides producing lots of corrosive residue to gum up the works.Muzzleloading rifled wpns before the minie ball required cleaning evry 20-40rds due to powder fouling preventing bullet seating.

Another thought.During the VN war an SOG program to sabotage ammunition called "eldest son" was instituted the plan being to salt battlefields/wpns caches with cartridges that had been sabotaged with a "white explosive powder similar to PETN but more sensitive(ETN,MHN etc?)"(exploding with the shock flame of a primer!Familiar materials?) Occaisonally AK47s-SKS's were found next to VC whose wpns had detonated in many cases driving the (sheared of locking lugs) bolt back into the firer's eyesocket along with a fragmented reciever.OT but this was also done with the propelling charge in mortar rounds which would sympathetically det.the main charge(82mm) killing the entire mortar battery.

I hope this post will cause you to rethink or at least delve a bit further into modern propellants and the numerous pitfalls
even with store bought components.

[Edited on 20-12-2011 by grndpndr]

[Edited on 20-12-2011 by grndpndr]

quicksilver - 20-12-2011 at 06:26

Quote: Originally posted by KINTF

Ok,

Could the smokeless gunpowder used for modern, self-loading weapons that contain cavities (gas pistons, etc) that could get stuck with some solid residue, be made out of something you could offer from this board? Are chlorates mixed with something a good choice or not?

It would simply be too hot (addition of another energetic) for a small scale bore. It MAY be possible to use existing TBSP in SOME .50 BMG's but the eventual wear would be substantial.

KINTF - 20-12-2011 at 22:12

For your convenience I have test environment that quarantees the safety for all individuals involved in the testing procedure. And yes, my goal is to discover propellant that is suitable for firearm use, at least in blowback or delayed blowback action.

For start I shall look for nitrocellulose, EGDN/PGDN and vaseline dissolved into acetone and made in to thin strings, according to the original cordite formula with improvization at the NG since it is too hazardous. I shall also test the chlorate as propellant.

hissingnoise - 21-12-2011 at 03:16

Quote:

I shall also test the chlorate as propellant.

Chlorate compositions are fulminating mixtures and cannot be used as propellants.
Berthollet found this out, to his cost, back in the eighteenth century . . .

grndpndr - 21-12-2011 at 10:31

IIRC there were successful early 'smokeless' propellants that utilized ammonium nitrate as a substitute for KNO3 /sulfur.I believe ammonpulver consisted of AN/charcoal
90/10 or therabouts supposedly cool burning.That could be a starting point.
Back to the safety aspect thats your concern but let me remind you self loading firarms utilizing gas systems as opposed to a straight blowback/bolt action/SS are very sensitive to gas port pressure.To much pressure and you may be wearing an operating rod as an occular and have severly damaged-destroyed a valuable weapon.Personally I think its a singularly bad idea
for an individual to presume he can manufacture a superior dbl/trpl base powder to a higher quality-better performing std than multimillion dollar companys spending yrs perfercting a propellant for a specific use.However if you have no reasonable alternative to buying factory made SP
I can empathise with the need.
All sid and done I wish you all the luck in the world and above all be safe?!

German w2 AC cannon

grndpndr - 22-12-2011 at 15:56

The germans were a generation ahead in the design of thier latest aircraft cannon/projectiles.They used a thin wall projectile that carryed a relatively large amount of explosive meant to deal with US/Brit Bombers so high pressure/velocity was not compatible with thier projectiles.Of course a single 30mm
german AC cannon shell would easily down a fighter aircraft.In fact german aircraft tech including gunnery was high priority spoils of war with many post war european jets using basically german designed 30-35mm rotary cannon.Unlike our hvy gatling gun w/multiple bbls the germans used a single bbl with a revolver like cylinder.So BBL heating would have been a huge concern w/o controlled bursts.high air speed cooling.FWIW

KINTF - 25-12-2011 at 05:17

We have CNC machines and rifling tools and licenses that we can mill custom made firing devices so if some of them blow up, it wont matter, actually we want to see what is the ultimate bearable strength of those devices under the tested propellants. We also want to test high explosives as propellants fired from ultra heavy constructed firing devices and see how it affects the ballistics.

During the years I have found out that where about all the things in the world you invent you will google and find that somebody invented a hundred years ago, but actually the phrase "it has always been done so" is poison. We need innovative and brave people who actually find and test things out and maybe learn by mistake, but sometimes make fantastic inventions. The army and weapons technology is in same situation in many ways - it has always been done so, and it will be. Not until somebody innovative comes to the office and puts everyting in new order.

grndpndr - 26-12-2011 at 19:02

OK? Caveman chemist to DWM in 6 posts.

You dont really believe military tech(in any area) has remained static do you?

[Edited on 27-12-2011 by grndpndr]

quicksilver - 27-12-2011 at 07:56

Quote: Originally posted by KINTF

Chlorates had been tested on many levels and for a lengthy period; unfortunately always demanding far more work, problems & inconsistencies.
During the mid to late 19th century chlorates were looked at as a means to bring black powder up to a much higher levels of speed and powder. Testing was a failure and during that "Black-Powder period" it was found that serious levels of speed (in burning could be achieved via the widest variable: charcoal. There are charcoals that can alter BP speed, etc to and order of magnitude from the original 75/15/10 !
One of most serious problems w/ chlorates is their very serious corrosive element & a spike-like pressure curve. Primers had been made from Chlorates right up through the twentieth century, but nothing could be done about the corrosion issue.

If you research chlorates and their relationship to BP you'd be quite astounded to see how many times and variations had been attempted - all with failure. but BP (through the use of proper mfg procedures and very unique charcoal) came close to NC pressures. The problem was - CONSISTENCY (& fouling of course).
The reason why Goex, etc make the rather tame powders they do is that from batch to batch they are remarkably consistent. When a barrel heats with many high explosives the pressure curve alters and thus accuracy goes down hill. Some BP can be remarkable in their power.

Attachment: BlackPowder41-b.pdf (2MB)
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[Edited on 27-12-2011 by quicksilver]

grndpndr - 27-12-2011 at 15:57

I just came across some descriptions of exactly what 'Qsilver'
has described.Ive heard it called 'brown powder', 'cocoa powder' etc (manual of explosives,military pyroyechnics and chemical warfare agents) over the years from various sources. From a manufacturing standpoint modern propellants(and even turn of the century equivalents) are not a simple mixture of chemicals but carefully granulated-sometimes perforated grains with a bewildering variety of stabilizers/deterrent coatings.By far the most simple formula that offers a single base NC performance envelope would be ammonpulver IMHO.
Single base NC powders are still relevant
and in everday sporting use. "IMR" powders by winchester(?)IIRC (im proved military rifle powders) come in several variations and are still widely used at least in the USA as a small arms propellant but I wouldnt be at all suprised if its equivalent isnt made OS as well.
Small arms AFAIK are pressure limited more so by cartridge case construction than mechanical strenght of the FA mechanism. A mild steel cart. case capable of containing higher pressure than a std brass case.Weak points in case construction can be case head seperation, primer pockets
primer cup-material-thickness themselves not being capable of containing the pressure and yielding before the strength of the mechanism. The high pressure gas leaks destroying the wpn as surely as a failure in the mechanism.

Ther closest thing I can imagine from your last post would be a HV/HP tank gun such as the 120mm abrams smooth bore tank gun. The veloc ity of its saboted projectile(1700MPS) is over 2x that of a 5.56x45 0r 7.62x51 projectile.And its operating pressure near 80,000 PSI versus approx 50,000 for NATO small arms ammo.Instead of a brass cartridge case it and wpns like it use steel cases and screw in electrically fired primers rather than the press fit percussion primers to cope with the pressure as well as very high strenghth breech mechanisms made of finest steels and latest heat treat tech.Lots of $ invested Powder composition is probably not widely known nor intended to be, simply described as a granular propellant.
Since you are interested in propellant advances youve likely heard of the US armys program to develop a quick firing cannon using a liquid propellant thats(obviously) injected into the firing chamber after the projectile.Thers no cartridge case which is not ususual for large naval cannons and some of the larger land cannons.They of course used an obturating pad and interrupted thread type breechblock to seal the breech.

Some great weapons designs have been made by the tabletop designer with basic notepad and selftaught drafting
'skills' combined with garage machinists w/minimal tools.The Barret 50BMG semi auto sniper rifle is just such an animal.An Idea combined with persistence (small bank loans) and he..MR Barret designed and manufactured basically as an indivcidual a wpn thats been adopted by a good majority of the worlds armys and coveted by most civilian shooters.So take my naysayers attitude for what its worth, defeatist.I just wanted to point out the difficultys no disrespect was intended.Best of luck to you in your endeavors

[Edited on 28-12-2011 by grndpndr]

[Edited on 28-12-2011 by grndpndr]

hissingnoise - 28-12-2011 at 04:23

'Cocoa powder', a relatively slow burning composition, made with an incompletely carbonised material, was dangerously friction-sensitive and its preparation shouldn't be attempted!

grndpndr - 28-12-2011 at 12:55

Do you have a reeference for that Hissingnoise?

Cocoa powder is the same propellant as brown powder
(incompletely carbonized charcoal)
cocoa only refers to the color.I have seen no references indicating Brown powder any more sensitive than black powder.In fact It replaced granulated black powder in British service among others.If the powder was so sensitive to friction its very doubtful it would have been approved for military use.

The more I read about ammonpulver the more it seems it could be an emergency substitute for commercial propellants
provided magnum primers or a small base charge of BP or SP
could be introduced prior to ammonpulver as its supposed to be difficult to ignite.
Performance wise its a near equivalent to ballistite containing 1/3 NG by wieght with a relatively cool burning temp of 900C versus NG's explosion temp of 3470C

'List of British Ordnance terms' Ehow
'Chemistry of Powder and explosives' Davis

hissingnoise - 28-12-2011 at 13:17

Quote:

Do you have a reeference for that Hissingnoise?

Not one I can point to now, grndpndr, but the article, IIRC, said the powder inflamed by being shaken in a stout cloth bag . . .
And brown powder was, at one time, prepared from partially carbonised straw - either barley or rye!

grndpndr - 28-12-2011 at 14:47

I can see BP doing the same in similar circumstances are you just saying that brown powder is sensitive like BP?

Im aware that brown powder was made using these materials I just dont understand why it would make them more sensitive to friction than BP.I wouldnt put either BP/BRWN P in a mortar and pestle in any event.Blk P dangerous to handle/ man. as well w/o proper precautions
Have a Happy-SAFE N/YRs "event"

hissingnoise/qsilver etc etc

[Edited on 28-12-2011 by grndpndr]

[Edited on 28-12-2011 by grndpndr]

hissingnoise - 28-12-2011 at 15:48

I know you've been through a lot in the past grndpndr - I hope you're well and I'd like to see you active here with the rest of us 'misfits' (for want of a better term?) for a long time yet!

Quote:

Have a Happy-SAFE N/YRs "event"

hissingnoise/qsilver etc etc

And I can only echo your sentiments and hope this coming new year will be a good one all round . . .

grndpndr - 28-12-2011 at 19:05

cant think of a better group of 'Misfits' to be assosciated with!

eyeofjake - 2-1-2012 at 23:15

You first need to realize is that Germany was always looking for new sources of propellant as they were on the losing end of supplies. Once they had 2 fronts to deal with, supplies got thinner for weapons. Unlike the US which had a steady supply of Nitrates and chemicals for explosive production. WWI alone would have been short if it wasn't for good ol Fritz Haber and his Haber process.

Also, aircraft weaponry and standard soldier weaponry differ greatly. Especially in build and design. Aircraft weapons are larger in caliber, require slower burning powders, can sustain much greater chamber pressures, and can be readily cooled by the heavy airflow in flight. Troop weapons are designed with small calibers, faster burning powders, and can't cool as fast. That plus ammunition carried by troops is expected to survive horrid conditions of rain, snow, mud..etc... Aircraft ammunition is sealed in the plane often and doesn't need to deal with such demands. So to use a PETN based propellant could be done sure, but to try and scale it to fire a 9mm or 5.56 mm round would be pointless. Smokeless powder does such a great job. It's clean (relatively, I always had to clean my rifle after laying down rounds), powerful, cheap, and effective.

The Germans were masters at coming up with great alternatives when needed. War has a way of bringing the best of improvisation out of people.