testimento
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Guanidine as gunpowder?
I read that nitroguanidine is used in triple-base gunpowders. Because gun powder in my country is higly restricted, I was wondering wether it could be
used as such, or combined with something else which can be made oneself. If one just packs powder form nitroguanidine into gunshell and fires is at
gunpowder, will it likely cause detonation, or would it burn consistently, providing thrust for the projectile? Since it seems to be quite easy to
make, I might get a thread breeched barrel blank and make some safety test firings with it later.
I also saw that RDX and PETN are used as well in mixtures. Are the mixes made so that all the components are dissolved into a solvent and then
evaporated to form an uniform crystalline/granulate mixture?
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Bert
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Making smokeless powder at home is not a good project. The technology needs to be very precise for repeatable results- You can lose body parts to an
exploded gun.
Guanadine nitrate isn't used in gun propellants by itself, it's added to powders to increase gas output and reduce muzzle flash. It burns with a
fairly low temperature gas output, especially compared to nitroglycerin and nitrocellulose
There were commercially made reloadable hobby rocket engines that used compressed pellets of nitroguanadine plus a few other ingredients. It was a
fairly low Isp but (relatively!) safe propellant in that use.
http://en.m.wikipedia.org/wiki/Jetex_engine
There is a good overview of smokeless propellant technology in Tenney Davis Chemistry of Powder and Explosives:
http://library.sciencemadness.org/library/books/the_chemistr...
[Edited on 4-2-2014 by Bert]
[Edited on 4-2-2014 by Bert]
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DubaiAmateurRocketry
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Talking about nitroguanidine, I was always interested in one of its derivatives, which is nitroguanidine's salts, one of them is nitroguanidine
nitrate.
Ive also found some people discussing about this few years ago on a post in this forum, however I cant find it. I also remember its synthesis and that
its pressed density could achieve 1.8 easily, which means it is dense. Heres its synthesis I remember from reading the post.
![](http://i58.tinypic.com/1dy0lc.jpg)
The final product has a CO oxygen balance of +14.4%, and its CO2 OB balance of +5%. I also predict its impact sensitivity to be less than other
proposed oxidizer such as ADN, HNF due to the hydrogen bonds. Since its pressed density could reach 1.8, it should be an competitive candidate for
green oxidizer. So what about its dinitramide salt? nitroguanidine is readily available which makes this attracting.
[Edited on 4-2-2014 by DubaiAmateurRocketry]
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franklyn
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" You can lose body parts to an exploded gun "
This old myth again. There is no documentation of any such occurrence.
( I wish ' The Wizard is In ' were around , no doubt could come up with just such a reference )
I am aware there have been very rare instances reported of breach failure. Uncomfortable for the shooter and ruinous for the weapon. I cannot account
for any homemade improvised firearm. Any firearm type manufactured in the 20 th century has been test fired with a proof round , which is a casing
crammed with powder , far beyond what any hand-loader would prudently put in.
The problem with improvised propellants is maintaining consistency of product. Gun Cotton is the most amenable for obtaining reliable results.
Metering the amount to be loaded into every cartridge is more the problem. One reason why propellants are made as corded powders. A few grains will
mean the difference between an accurate and reliable load , or else one which will vary in consistent performance. Often the result of too little
powder or sometimes inadequate primers.
Citric acid has seen experimentation as an ingredient mixed with oxidizers. One can purchase 2500 gms for $ 27.
Related topics
www.sciencemadness.org/talk/viewthread.php?tid=9443#pid17013...
www.sciencemadness.org/talk/viewthread.php?tid=14033#pid1891...
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Bert
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Quote: |
" You can lose body parts to an exploded gun " This old myth again. There is no documentation of any such occurrence.
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Franklyn- I've been shooting since 1968 and reloading ammo since 1979. I have tried to learn as much as I can about the subject, rather than merely
treating the various manuals as a collection of recipes. I also work with explosives as my "day job" and my primary consideration there must always be
safety.
Modern weapons can indeed be blown up by improper choice of either type or quantity of propellant. The use of fast burning powders such as Bullseye in
economical target pistol and rifle loads where a case can easily hold double or even a triple charge has led to destroyed weapons and injured
shooters. Inexperienceed reloaders choosing the wrong type and/or quantity of propellant, mislabeling of re-packaged powders and use of improper types
of ammunition have all led to even strong modern bolt action rifles being destroyed. Eyes, fingers and parts of hands have been lost.
Neither the occurence of such incidents or of harm to the shooter are myths.
A person who has no experience in ammunition reloading and lives somewhere he apparently has no culture of such artificers to learn from asked about
making propellants. He mentioned use of RDX and PETN in propellants as well, for which syntheses from OTC chemicals are available on this forum and
possibly within his capabilities.
I do not think my response was wrong either factually or in spirit. If you wish to discuss this further, let us proceed via PM.
[Edited on 5-2-2014 by Bert]
[Edited on 5-2-2014 by Bert]
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A little PETN in a sandard cartridge can do some serious damage to shooter and weapon alike. This has been used as a weapon before:
http://en.wikipedia.org/wiki/Project_Eldest_Son
Even putting fast pistol powder in a rifle cartridge is asking for trouble, and IIRC the major difference is simply grain size and shape. Black powder
muzzle loaders are proofed, and will readily explode when introduced to smokeless powder.
Any HE, nitroguanidine included, is going to far exceed a proof round in chamber pressure unless specially blended with moderants and carefully
controlled with respect to grain surface area - something difficult if not impossible to do at home.
Heck, a M1 proof round in .50bmg is rated for 65,000 PSI... and consider that calculated max explosion pressures for HEs are in the order of 5 or 6
million PSI. Sure, packing density and "real world" adibatic expansion reduces this, but it's pretty easy to go wrong when you can
potentially exceed a proof round by a factor of 80, should your propellant go high order.
Also, franklyn, you should type "hurt in rifle explosion" into Google sometime.
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franklyn
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I maintain that without exception catastrophic failure is always attributable to faulty mechanical mating of the
bolt to the breach inadequately supporting the case head , not pressure overshoot although this can of course be decisive for a marginal and therefore
inherently unsafe gun. Detonating high explosive in a chambered round is not ever done unless you're loco. Propellants cannot go high order which is
why they are propellants.
www.sciencemadness.org/talk/viewthread.php?tid=22649
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Agreed, and the original suggestion was to fill a cartridge with the high explosive nitroguanidine. No bueno.
I disagree:
Detonation of double based smokeless powder (SciMad thread)
From the BATFE regarding ammonium perchlorate composite propellant:
low explosives/propellants ‘. . . are used primarily for propulsion purposes . . . [and] normally function by burning rather than detonation, [but
that] many propellants are susceptible to detonation.’ .
Sure, they're engineered not to detonate. I get it. Unfortunately, the type of processing required to make NC/NQ/NG not detonate is probably
beyond the amateur. We're talking about stuffing nitroguanidine in a rifle cartridge here. The worst case scenario is that it actually works for the
first few times, then goes high order and takes poor testimento's face off.
I will not say it shouldn't be tried; however—if you enjoy life—stand well back.
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Bert
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Quote: |
Propellants cannot go high order which is why they are propellants.
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Propellants can be made to detonate, I've done it deliberately. You have seen it done too, I believe. Remember Axt? His nice videos of blasting caps
in lightly confined samples of various smokeless powders?
http://www.youtube.com/watch?v=qTwdg6XejpU&feature
Propellants don't need to undergo detonation to destroy a gun in any case. Steel is only so strong.
Modern powders are carefully designed and tested to burn in an orderly fashion under certain parameters. If you burn them outside of their design
parameters, they can and have exhibited pressure curves that destroy actions before the projectile even moves down the barrel.
Don't believe that? Take a pre WWII 30-06 blank cartridge. Remove the forward closure and install a .30 projectile in the case neck, chamber it in a
1903 Springfield and fire it. More than one serviceman had that bright idea back in the day-
The afore mentioned double/triple/quadruple charging of a case with Bullseye or similar is common enough that powder fill depth check mechanisms with
audible alarms are sold for several models of progressive presses. Ask anyone with a couple of decades experience in high volume bullseye shooting- If
they haven't wrecked a pistol doing it themselves, they certainly know someone who has.
Reloaders can and have destroyed weapons with small charges of slow burning powders as well. The technicians and engineers who work developing manuals
for reloaders believe this, you will find warnings not to go below a certain percentage of case fill with such powders. Google on SEE: Secondary
Explosion Effect
Quote: |
I maintain that without exception catastrophic failure is always attributable to faulty mechanical mating of the bolt to the breach inadequately
supporting the case head , not pressure overshoot
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Perhaps you could call several gunsmiths at random from the yellow pages and ask them it they agree?
My idiot younger brother split the cylinder, stretched the frame and tore apart the forcing cone of a very nice new revolver before he was 16. It's a
little tough to fire a revolver in an unlocked breech condition, Franklyn! He loaded several .357 mag cartridges nearly to the top with an unweighed
charge of a fast burning double base shotgun powder and a jacketed bullet. The 3rd shot took the gun apart
If you can't find evidence that improper loading can and has destroyed weapons regardless of the weapons breech properly locking as designed, it is
due to your not looking. Here's some photos- Notice the bolt is still locked to the action?
http://thefiringline.com/forums/showthread.php?t=341348
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franklyn
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Strother Martin said it best - Click on the image
![](http://upload.wikimedia.org/wikipedia/en/8/8c/Cool_Hand_Luke_Martin.jpg)
Detonation has a technical definition which I refer to that is not the colloquial misusage meaning an explosion.
You must be aware that secondary explosives have a minimal critical diameter for a charge to high order. These are in the range of artillery sized
calibers. The content would also need to have been pressed at 20 to 30 thousand pounds per square inch into a solid mass. There is a condition which
is conjectured that on ignition , unreacted powder ahead may be hammered forward and compressed such that it can propagate a detonation wave. This
remains undetermined from what I know.
The video of exploded loads while violent and very dramatic , do not show detonation of any kind. You can readily tell just by the result. You end up
with one , two or three big pieces. Had actual detonation occurred there would not be any part of the containment in sight , having been fragmented
into particles thrown tens of yards away. Confined deflagration is not detonation. Conditions for even low order , attained at the instant all the
powder is already consumed , is a mute point.
I have no quarrel with the fact that just as a pipe bomb produces an explosion so too on a smaller scale a cartridge can do the same. What is
contained in a casing between the bullet base and the primer is half the story. The mechanical reasons are encyclopedic in scope , with such
contributors as a heavy weight bullet , head spacing to far forward or bullet seated too deep. The extent of use any particular gun has had prior to
failure , since over time the metal is weakened with use. Pistols such as the Browning 1911 pattern .45 caliber Colt automatic are notorious for it's
design defect , the poorly supported case head at the feed ramp. This has been remediated by thicker case heads as with the .45 super and the slightly
longer .45 Detonics 'magnum'. The .45 Winchester magnum which predates it being the longer 'magnum' version based on the same cut down .308 rifle
brass. True magnum hunting rifles have belted heads to afford even greater ability to withstand elevated pressure.
You might be interested to know that it is entirely feasible to fire an ordinary bolt action in automatic mode from an open bolt position. All that's
necessary is to attach bungi cord to the upright bolt handle and have a fixed firing pin. Draw back the bolt and release it on a chambered round and
rock and roll. Locking is not necessary providing the bolt has sufficient forward momentum when it slams shut to counter blowback.
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Bert
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Sigh.
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Scientwisted
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I'm not sure how this debate evolved to where it is now but I agree that nitroguanidine should not be used as a propellant unless like Bert said there
are other propellants in greater number and you have precise manufacture methods and strict QC implemented. Detonation in the previously mentioned
cartridge seems like a good possibility. To illustrate this check out "project eldest son" the military purposely switched out a few bullets from the
enemy's weapon cache and replaced them with tampered rounds with high explosive propellant. Used as a form of unconventional warfare by the US SOG in
I believe the Vietnam war it scared the shit out of the enemy and made them not trust their weapons source.- check it out
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franklyn
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Attachment: Deflagration to Detonation.zip (142kB) This file has been downloaded 435 times
Well over a century of research and development into primary explosives , detonators and blasting caps has been
in vain if detonation
could be simply achieved with a metal tube filled with propellant powder. As the above excerpts show one finds minor mention in
literature that detonation of propellants may occur only when confined in kilogram quantities or when initiated by a booster explosive
or ( such as this following experimental investigation ) explosives confined in solid columns of half an inch or wider after developing a
pressure of half a million pounds deflagrating over an interval of several inches.
See Transition from Deflagration to Detonation , page 12-13 to 12-20 here _
Engineering Design Handbook - Principles of Explosive Behavior AMCP 706-180
www.dtic.mil/dtic/tr/fulltext/u2/900260.pdf
Concerning the Question of Transition of Burning of Explosives to Explosion
Chapter 3 article 37 See the pdf page 763 here _
Theory of Explosives ( articles )
www.dtic.mil/dtic/tr/fulltext/u2/605706.pdf
As an example , assuming a small arm of 0.4 inch bore with a barrel or cylinder wall thickness of 0.15 inch. Tensile strength of steel
runs from 180 - 210 thousand pounds per square inch. For 200 times 0.15 means the barrel can withstand only 30,000 pounds of
tension circumferentially. 40,000 pounds per square inch chamber pressure develops over 17,000 pounds of circumferential tensile
loading. Doubling the chamber pressure to 80,000 also doubles the circumferential loading to 34,000 pounds , exceeding the burst
strength of the barrel. This mode of failure though rare is what is observed. Tungsten has a tensil strength of 510,000 pounds per
square inch and would easily withstand twice that higher chamber pressure - 160,000 pounds per square inch. For a greater margin
you simply increase the wall thickness. 0.2 inch would hold up at well over 200,000 pounds chamber pressure. At higher pressures
the material yield strength becomes a problem , the surface is peened and plastically deformed.
Robust firearms have been contrived to withstand elevated chamber pressures and are necessarily heavily built.
These handguns operate at internal ballistics characteristic of magnum rifles.
• In the 1950's, Utah gunsmith Dick Casull was trying to create a new cartridge , a .45 Magnum , capable of sending a 230 grain
bullet at 1800 fps , so he rapidly become a collector of cracked revolver cylinders , as none of them were able to cope with the high
pressures generated by his new cartridge. So Casull began manufacturing his own five shot cylinders , custom fitting them in Ruger
frames , the only ones able to withstand the new round. Finally, in 1979, Dick Casull and Wayne Baker created Freedom Arms ,
offering their first model 87 single action revolver in 1983 , firing the new cartridge .454 Casull.
• Another contender for ballistic extravagance designed by Max Gera , was the recoil operated Automag pistol built to fire high
pressure .44 AMP rounds exceeding the Remington .44 magnum. Harry Sanford began initial production in 1971 , resuming under
a new company reorganized in 1974 , ending the run in 1982.
• Wildey J. Moore a contemporary maker still produces a gas operated pistol , the Wildey , firing the .475 Wildey Magnum.
• Bernard C. White of Magnum Research designed the Desert Eagle pistol manufactured by Israel Military Industries. Originally
chambered to fire Remington .44 magnum , it introduced a new cartridge the .50 Action Express.
Related Post and Thread _
www.sciencemadness.org/talk/viewthread.php?tid=13283&pag...
www.sciencemadness.org/talk/viewthread.php?tid=17483
________________________________________________
Anyone interested in exploring the limits of ballistic performance can do so with assurance ( no guess work )
by adapting a strain gauge when working up to a high pressure load.
www.shootingsoftware.com/pressure.htm
.
[Edited on 14-2-2014 by franklyn]
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Bert
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I am happy to see you have researched these matters.
You may also wish to look up Elmer Keith and his part in development of the .44 Remington magnum. Keith blew up revolvers a plenty, back before cheap,
light weight digital instrumentation.
He also enjoyed making strong (outrageous?) statements not necessarily rooted in fact- It got him more page views, and made publications featuring his
work money.
Rapopart’s Rules for critical commentary:
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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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franklyn
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This is Lamé’s equation for circumferential tension ,
this online calculator evaluates the other two stresses also
www.engineeringtoolbox.com/stress-thick-walled-tube-d_949.html
This is Barlow's formula for burst strength , compute with this online calculator
www.corrosionmaterials.com/technicalInfoBurstPressureCalc.action
The several formulas outlined , both links serve the same pdf
www.hydraulicsupermarket.com/upload/db_documents_doc_21.pdf
www.pirate4x4.com/tech/billavista/PR-Hydro_Steering/Hydraulic Supermarket tech info -
Hydraulic Tubing.pdf
___________________________________________________________________
Keith was comparatively conservative compared to the wild things done at the National Labs.
Here is a report on a ' single shot ' three stage light gas gun they built. Quoted below from page 9
On How to Make The Fastest Gun in the West
* You must append ( .pdf ) to the end of the file name to view it
www.osti.gov/scitech/servlets/purl/301926
" peak pressure in the third stage transition region is almost 5 Gigapascals ( 735,000 pounds per square inch )
and is roughly 2 GPa along an - 1.5 m-long section immediately downstream. These values are well above the
burst pressure of any known barrel material. The barrel is designed therefore to survive long enough for the
projectile to exit." ![:)](./images/smilies/smile.gif)
This principle of a single shot sacrificial barrel readily lends itself to a single use disposable handgun comprised
of a single monolithic part with preloaded boreholes each fired sequentially. The more things change ,
the more they stay the same. - www.genitron.com/Unique-Handgun/15/Mariette-Pepperbox-Pistol
These ancient designs could readily be copied , improved and 3D printed in carbon fiber reinforced polymer
www.freepatentsonline.com/4646615.html , www.google.co.id/patents/US4685236
Another approach would be a replaceable cylinder of preloaded barrels , instead of a speedloader.
3D Printed Pepperbox Pistol - www.thefirearmblog.com/blog/2013/10/08/3d-printed-pepperbox-...
http://reason.com/blog/2013/09/11/3d-printing-enthusiast-unv...
www.guns.com/2013/07/01/3d-printing-community-updates-libera...
10 shot .22 pepperbox - Click on image
![](http://www.gunsamerica.com/UserImages/139138/994725567/pop_wm_3820819.jpg)
Oddly the impetus for contemporary firearm innovation has been governmental encroachment of self defense.
Disposable handguns are entirely defensive in concept and will become as common place as keychains.
This one's for preppers. Just as in antiquity when grain mills were communal affairs where everyone would bring
their grain to be turned into flour , so too a community of shooters could time share this. It would be the making
of a lucrative small business too , turning out custom rounds for members , turnkey and completely automated.
www.thefirearmblog.com/blog/2014/01/14/reloaders-dream-ammo-...
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testimento
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Hopefully nobody though I'd be loading firearm to my shoulder with mag full of guanidine rounds. Instead I would make custom-made thread breeched
reamed barrel blank for the experiment, using remote control to fire the round and measure FPS and check bullet and case condition after firing. I
would do hundreds of test shots with 0% failure rate before even considering firing it from any real gun, and even then I would operate it remotedly
for another hundred, even thousand. The objective of this idea would be to find a possible substitute for factory gunpowder, not a substitute for
hobbyist for good days, and to find out, is it ACTUALLY possible to manufacture own gunpowder with reasonable budget.
Yes, I am still interested. I read that guanidine is used in commercial rounds, mostly larger bore equipment, but as far as it would be manageable
from generally available materials, it would fit. I have read that nitrocellulose can be detonated, but in casing it will go deflagration.
So, we all know guns will blow up if you detonate HE inside them and they're dangerous when mishandled. How if we would discuss the possible
properties and compositions of improvised propellants suitable for semi-automatic weaponry? We won't be testing any of these without proper safety
precautions, so any ideas are very welcome.
[Edited on 18-2-2014 by testimento]
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Bert
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Mood: " I think we are all going to die. I think that love is an illusion. We are flawed, my darling".
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Good luck with the project-
If you want to fire a semi auto weapon, you will need a propellant with similar gas output and pressure/time curve as what it was designed to run on.
Oddly enough, that's likely to be made from the same things and in the same geometries as the original commercial/military propellants...
Re-inventing the wheel is fun, you can learn a lot. Did you download Tenney Davis and read the chapters on propellants?
http://library.sciencemadness.org/library/books/the_chemistr...
As far as "reasonable budget", if you want a workable, uniform and long storage stable product at near the cost of existing industrial products-
Probably not.
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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testimento
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There are some arguments on Wiki:
"Currently, propellants using nitrocellulose (detonation velocity 7,300 m/s) (typically an ether-alcohol colloid of nitrocellulose) as the sole
explosive propellant ingredient are described as single-base powder.[16]
Propellants mixtures containing nitrocellulose and nitroglycerin (detonation velocity 7,700 m/s) as explosive propellant ingredients are known as
double-base powder.[17]
During the 1930s triple-base propellant containing nitrocellulose, nitroglycerin, and a substantial quantity of nitroguanidine (detonation velocity
8,200 m/s) as explosive propellant ingredients was developed. These propellant mixtures have reduced flash and flame temperature without sacrificing
chamber pressure compared to single and double base propellants, albeit at the cost of more smoke.
In practice, triple base propellants are reserved mainly for large caliber ammunition such as used in (naval) artillery and tank guns. During World
War II it had some use by British artillery. After that war it became the standard propellant in all British large caliber ammunition designs except
small-arms. Most western nations, except the United States, followed a similar path.
In the late 20th century new propellant formulations started to appear. These are based on nitroguanidine and high explosives of the RDX (detonation
velocity 8,750 m/s) type."
I am aware that there is a mixture of approx. 35% nitrocellulose and 65% PETN which is called "nipolit" powder. The text above indicates that a
plausible mixture consisting nitroguanidine and PETN/RDX could be manufactured in ratio of 35:65 to 45:55. This is certainly something worth testing.
The most interesting part of this is that nitroguanidine can be made from ammonium nitrate and urea with treatment on sulfuric acid, and PETN can be
made by direct nitration of pentaerythritol with fuming nitric acid at correct temperature, and so on goes for RDX with far more OTC hexamine.
I was planning on making a 9x19mm and 223 bore testing blanks with 30mm cylinder diameter and breech lock with hand-installable metric threading(M30
thread) so that it would be more than strong enough to contain the blast pressure if the containments were to detonate. I would measure the muzzle
velocity of the projectile and see for any overpressure signs or deformations in the casings and run several dozens of tests before even considering
to move into authentic gun conditions. Semi-automatic firearms pressure and recoil operated mechanisms can be altered by adjusting the gas ports(gas
piston, direct impingement), or by adjusting the mass and spring load of open bolt actions. Certain arms, like AR15 and AK can be made to operate with
quite soft loads by adjusting the gas port, for ex. subsonic purposes. This requires the installation of adjustable gas port, which is not a problem
at all.
Has anyone seen any patents or similar scientific data regarding smokeless powder mixtures and components?
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