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Author: Subject: Picric acid: different instructions
grndpndr
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[*] posted on 24-6-2010 at 01:24


Some DBSP will detonate if confined in a very strong container such as a steel pipe. A 3-7% 325-425 mesh or finer flake AL should ease detonation.IIRC Hercules Bullseye pistol powder
w/a few % of flake AL detonates around 5500 MPS,not nearly enough for a SC more of a ditching grade HE.Im not sure (NM)
Nitromethane? will be sensitized by DBSP or if NM will plasticize
DBSP?If acetone is needed to plasticize the DBSP will the NM
evaporate before the acetone since I believe the acetone will desensitize NM?
In the shaped charge sticky the first few pages deal witha simple NM/AN/SA (Sulfuric acid) mix thats very effective in SC's and simple.
Or If you can nitrate Picric acid a mix of PA/NM is more than adequate for SC's.US Patent 5140908 describes NM/PA w/A wieght ratio of 53.5/46.5 the PA essentailly dissolving in the NM resulting in a liquid explosive giving excellent contact/consistency w/device.US patent 45634480 discloses the preperation of an explosive consisting of a mix of PA/NA (nitric acid) also a liquid with exc VOD and probably as important, excellent consistency of explosive w/device.

As said I used KNO3 for the first time w/mixed results v NaNO3
synthesising an old yellow dye although I modifyed the most difficult mixing process such as mixing the asa completely/thoroughly by using a variable speed drill with a simple formed glass mixing rod in the shape of a pyramid.No more laborious mixing with a stir rod to mix stubborn asa or the nitrate.Quicker mixing than description.My homemade overhead stirrer will be done soon anyway making other more mixing intensive synthesis more enjoyable.Ive seen few TNP eutectics or even compatible mixes OT mono nitro napthalene,
DNP por what seem to be difficult nitrations involving benzene
difficult to find precursors.

[Edited on 24-6-2010 by grndpndr]
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[*] posted on 24-6-2010 at 09:19


Solid nitrates utility in making a mixed acid is often complicated by the physical composition, time & temp of the materials. If the solid is reduced to a small particulate powder and the mixing method is altered; HN4, Na, & KNO3 all will work fairly similar w/ only the weight being the disparity. But it seems each has it's idiosyncrasies. Sometimes it's to an advantage to leave the mixed material in a refrigerated state for quite a few hours to complete the agenda. In some instances raising the temp to 40C gives better results. I believe the above nitrates will all produce a usable product but each has it's needs when mixing. This excludes the possibility that some solids are just too compromised with contaminants to do an adequate job.
If non-prilled alkali nitrate does not easily go into solution (mixed acid) I would look to the possibility of a contaminant after other avenues of mixing have been explored. I once attempted to use all OTC materials and found that a certain stump-remover had a greater amount of clay covering the prill than I would have imagined. This set most picric acid attempts to a less than pure state no matter what I did to correct the lab. It was only discovered when I re-crystallized the nitrate and found a great deal of insoluble material.




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[*] posted on 24-6-2010 at 11:27


After my last experience w/many failed synthesis after what seemed such a simple procedure using a fert grade NaNO3 an deciding to crystalized/purify the different brand of fert na nitrate I was absolutely shocked by the amount of impuritys (clay being the only identifiable impurity) I recover a bit over half 2lbs 2oz from a 4lb sack!!And this wasnt a sloppy procedure but carefully done so I expect very little nitrate was wasted.Thats the story of approx 3-4 failed synthesis.The KNO3
was a tech grade and despite careful additions there was considerable nox fumes but the synthesis was successful.I also cheated a bit with this last synthesis.I used a variable speed drill
with a glass rod bent to a pyramid configuration,stirred hell out of the asa/H2S04/ saving alot of elbow grease as the asa has always been as pain for me to properly mix/sulfonate ASA the drill took the problem out of that.The overhead stirrer Im working on for problems (ETN) and long stirring times should ease and simplify the entire synthesis freeing my hands for other tasks.Only real questions are are compatibility problems w/TNP?Mononitronapthalene of course makes a good eutectic/TNP of course with a reasonable VOD of over 7000 MPS.
But another nitration of napthalene with the accompanying extra work! also Ive yet to find a compatible eutectic that gives
= power/brisance to plain TNP. Other than something like DNB?
Which makes it more like a primary in terms of sensitivity! NOT acceptable! ETN! whats compatible with it? Could AN be used as a melt/composition similar to a TNT/AN?Im aware the AN wouldnt melt but a well mixed AN/ETN melt comp would hold the granules of AN and perhaps AL flakes in a well mixed comp.
Hopefully with an even better power/brisance than an amatol?
Any thoughts. also as to detonability of a ETN/AN/AL.

[Edited on 24-6-2010 by grndpndr]
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[*] posted on 24-6-2010 at 13:33


The KNO3 I used in earlier experiments was USP grade, not fertilizer grade, it also dissolves completely and easily in water. The nitration solution gets very thick quite quickly and results in less nitration efficiency, and quality of product (in my opinion). I am not saying it can't be done successfully with KNO3(high purity product in high yeild), but I do think it will take more H2SO4 and a lot more work.

The NH4NO3 I used in earlier experiments was 34-0-0(fertilizer), and until I used it to make the NaNO3 recently, I was unaware of the amount of crap in it. I used 1.5 mol of baking soda, and 1.5 mol of NH4NO3, to make 1.5 mol of NaNO3. It was when I filtered the NH4NO3 solution that I noticed the slimy gunk on the filter paper (not what I want in my reactions). I always got poor yields and an annoying amount of oxidation products with NH4NO3, but I should have of course purified my 34-0-0.

I found the NaNO3 to be a clear winner in a TNP synthesis, but it is true that my process may not have been well adapted for the other nitrates.


[Edited on 24-6-2010 by Hennig Brand]
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[*] posted on 24-7-2010 at 16:59


Just for fun, here is an old barrel I found and put to good use. I like to call this photo "Barrel Blasting".

The hole on the [left] was made with 2g of Picric Acid in a 3/8"ID Aluminum tube, set off with 0.4g of Lead Azide pressed on top of the TNP. Safety fuse was used, and a vise for pressing.

The hole on the [right] was made with 1.5g of ETN, 0.1-0.15g of Lead Azide was used to initiate it. A 1/4" ID parrallel wound paper tube was used. It is always very impressive stuff.

The whole in the [center] was made with 40g of a gellitin dynamite, in a 3cm diameter pill bottle(plastic). Approx 15g NG, 0.6g homemade NC. Acetone was used to facilitate NC dissolution. Also 20g KNO3, 4g sugar(sucrose) ground fine together in coffee grinder before mixing in with gellitin. This mix is one of my favorites, although I normally use aluminum powder in place of the sugar, which does seem to make quite a difference in performance, or at least a lot better boom:). I quite often go with NH4NO3 instead of KNO3 as it is a much better gas producer(and cheaper), but it doesn't produce near the heat as KNO3 which is losy when using Al powder. A 1/4" parrallel wound paper cap was used, with 0.6g HMTD pressed inside as a detonator, and safety fuse.

I felt the TNP should have done better, though the TNP charge was not spread out over as much of an area as the ETN. Maybe it wasn't set off properly? It doesn't mean it isn't a good initiator, even if it isn't the most powerful, I guess.

BTW the barrel is made of some fairly tough steel, 1/16" as measured with vernier calipers.

Barrel blasting 001.jpg - 190kB

[Edited on 25-7-2010 by Hennig Brand]
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[*] posted on 25-7-2010 at 06:11


Quote: Originally posted by Hennig Brand  

The whole in the [center] was made with 40g of a gellitin dynamite, in a 3cm diameter pill bottle(plastic). Approx 15g NG, 0.6g homemade NC. Acetone was used to facilitate NC dissolution. Also 20g KNO3, 4g sugar(sucrose) ground fine together in coffee grinder before mixing in with gellitin. This mix is one of my favorites, although I normally use aluminum powder in place of the sugar, which does seem to make quite a difference in performance, or at least a lot better boom:).



The issue of whether aluminum (which would raise the temp of the detonation) has a substantial impact on the effectiveness of an energetic is an interesting subject in itself.

Generally, testing from Sandia Corp & Los Alamos indicated that the result [of the addition of powdered Al] was a higher temperature but slightly less speed. Yet the use of temperature enhancing materials such as Al is a common feature in both military and commercial materials.
One of the more interesting tests were the use of Al in the enhancements of "cool" explosives such as nitroguanadine. One of the performance theories is that due to a rise in heat, the blast-wave "spreads" quickly (as opposed to a lower temp wave front). This is pretty logical since heat generally lowers density.

Powdered Al had also often found it's way into modern (non-fulminate) detonators. It's principal use there was as a "lubricant" during the construction of the detonator, to facilitate packing with a lessening of friction. It apparently did it's job quite well as it's still illustrated in film clips about detonator construction.


edit:
- Pretty impressive pictures.
I was also quite lucky to snag some USP KNO3 and it's use in a variety of things has been great. It was really worth the hassle getting it.
If I ever break down & buy a digital camera I'm going to try find one with some level of macro capability. A strong close up of the metallic tears would have been very interesting.



[Edited on 25-7-2010 by quicksilver]




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[*] posted on 25-7-2010 at 07:23


I always sort of wondered if putting Al powder in AN based explosives was kind of a waste because of the low heat of detonation. Maybe the ones with high concentrations of Nitric Esters or Nitrated Aromatics would get much more potential out of the Al powder.

Anyway here is a close(r) up picture of the hole the 2g of TNP made(2g TNP compound cap #1). Does anyone know if this seems like a reasonable amount of damage for 2g of TNP? It seems a little wimpy. Anyone with first hand experience, your opinion would be valued.


TNP blast hole.jpg - 173kB

[Edited on 26-7-2010 by Hennig Brand]
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[*] posted on 25-7-2010 at 07:27


Here is a close(r) up picture of the hole the 1.5g of ETN made. Note that the ETN actually ripped the metal right out for the most part(I love this stuff).

ETN blast hole.jpg - 131kB
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[*] posted on 25-7-2010 at 07:32


Here is a close(r) up picture of a section of the rather large hole the ~40g of KNO3 gelatin dynamite made. It made a huge hole, but the metal was mostly just all curled up. I could not uncurl the metal by hand.

Dynamite torn metal.jpg - 159kB

[Edited on 26-7-2010 by Hennig Brand]
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[*] posted on 25-7-2010 at 09:47


I'd assume that you didn't get a full det out of the TNP.. It is quite insensitive and needs a lot of initiating power to get it to kick. The hole is probably from just the primary and a very small amount of TNP.. Try more primary or press a TNP base, then a 50/50 TNP/ primary , then your primary( kind of like a step prime)..

[Edited on 25-7-2010 by pjig]
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[*] posted on 25-7-2010 at 14:41


You are on the right track, or at least my couple small tests would seem to indicate that.

I tried just the 0.4g of Lead azide in a cap to see what the effect would be on the barrel, and it hardly left a scratch.

I then made another cap with 2g of Picric Acid just as before, however this time I used 0.6g of Lead azide and 0.1-0.2g of Basic Lead Picrate as a flash igniter lightly pressed on top of the Lead Azide to ensure rapid and uniform ignition of the LA(I wanted to be sure).

Before even going to check the barrel, just by the sound I could tell I had a much better result. The hole is a lot bigger than before though a little smaller than what was made by the 1.5g of ETN, it did tear the metal right out in much the same way.

I guess I had a lower order detonation the first time. My Al tubing is pretty soft and thin, so the confinement is probably a little less than optimal. Also the LA from my last batch was kind of darker brown than normal, so maybe not up to normal standards (I don't know for sure, I guess I could test different samples to be sure). Anyway both TNP and LA were pressed untill the Al started to buckle. While 0.6g LA seems like a lot of primary to get TNP to really kick, when it does kick it kicks pretty darn well.

Here is a picture of the hole made by the second 2g of TNP(TNP compound cap #2), in the same barrel (I just rotated and exposed a fresh face).

TNP overdriven.jpg - 175kB

[Edited on 26-7-2010 by Hennig Brand]
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[*] posted on 26-7-2010 at 05:19


Quote: Originally posted by Hennig Brand  

Anyway here is a close(r) up picture of the hole the 2g of TNP made. Does anyone know if this seems like a reasonable amount of damage for 2g of TNP?


There are simply too many variables to be blunt & say: " 2 gr of TNP should look like this or that when detonated against 16ga sheet steel".
An appropriate illustration would have to take into account the direction of the cap, it's proximity to the barrel, the density of the TNP, the construction of the charge as a whole, & the phenomenon of ignition.

We know that TNP is generally a squeak stronger than TNT, so using that as a basis for comparison, the best agenda is to find TNT test results and see if you're in the ballpark.
I certainly think that IF the TNP were pure, you're on the money.

Does the TNP "pop" when struck on an anvil w/ a steel hammer? That's a cheap & easy way to know that you have little to no DNP in with it.
Make two caps with the TNP sample as a base charge. One with two gr and other with 4gr. If you see similar results and then a greater witness-plate hole; you know you are getting appropriate response from the TNP and not the det cap obscuring the results.




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[*] posted on 26-7-2010 at 06:19


My last post shows much better results from 2g of the same TNP.

It is the TNP from the picture(my first picture of the coffee filter and 43g TNP, big crystals), made from ASA and NaNO3.

It does go snap with a firm wallop of a heavy hammer.

I should have said before, but when the Al starts to buckle I have pressed the TNP to ~1.4-1.5g/cc (in the ball park anyway, calculated using volume and mass).

There was no tamping, the compound cap was just laid on the barrel, and held in place with a bit of tape.

The first 2g TNP compound cap was definately a low order and/or partial detonation, but the last 2g TNP test(from the last picture and post) did much better(similar brisance it seemed to the ETN).

It seems that what I have read about TNP is true and it will tend to go low order unless overdriven quite a bit (most likely especially true in small quantities of TNP). I believe Rosco has discussed the need to overdrive TNP several times that I am aware as well.

Just realized that maybe I didn't differentiate very well in my posts the two different TNP tests. I labeled the two a little better now.


[Edited on 26-7-2010 by Hennig Brand]
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[*] posted on 26-7-2010 at 16:15


In the most precision and optimized cap I can make, I customarily overdrive a base charge by a minimum of 50% over the amount which is the minimum found will 10 out of 10 tests reliably produce a high order detonation. If it is a more improvised sort of configuration, then 100% or even more than the minimum ...
yepper double it ...and suffer no misfires as the reward for such "wastefulness".
When it comes to "economy" there is good economy and there is senseless economy. When it comes to explosives, and a few other things actually, it is better in my opinion to be sure you have "enough" by using a little "extra" than to come up short....it isn't like the "patient' is expected to survive the operation,
but generally is just the opposite idea, unless it some kind of anomalous "special application" scenario where surgical precision and selectivity is required....then blow the hell out of it, to make sure it is thoroughly well blown. Most of the time when you drop a light bulb onto a concrete floor it will shatter to pieces, but on rare occasion one will bounce instead of breaking. If the occasional anomalous uncertainty of a love tap is unbearable, a sledgehammer reliably removes all doubt.

In terms of velocity and brisance ETN would be expected to do better than PA. But there are other things that PA can do better, storage stability being one, and lower sensitivity being another. Really these are different types and class of explosives so it is apples and oranges beyond the fact that they are both energetic materials. ETN may be thought of as a generally similar explosive to nitroglycerin, a bit less stable, and in solid form. And PA is more of a TNT class material, so the parallel comparing ETN and PA is much like comparing NG and TNT.

[Edited on 27-7-2010 by Rosco Bodine]
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[*] posted on 26-7-2010 at 17:47


Thanks for the input. My caps are definately not perfectly optimized, most likely from every perspective there is, but as you say they can be made to work.

So 0.6g LA doesn't necessarily seem all that excessive in my case then?

It is pretty impressive stuff(TNP) when it does detonate high order, love the sound, and the carnage;)

BTW, I have lately been experimenting with Basic Lead Picrate and found it to detonate very easily from flame and a bit of confinement, but mine seems very resistant to concussive ignition(wack with hammer). It it normal? I have always read the stories of it being supper sensitive, but then again many say that about pure TNP also.
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[*] posted on 27-7-2010 at 06:28


As you've most likely read, well made lead azide can be brought down to an extremely light weight as an initiator to PETN; this is also likely toward more sensitive materials such as ETN. The level of initiator weight for picric acid may be similar to TNT and I would be fairly sure that your needs are much less than over half a gram.

Factors such as the level of density of your base explosive, the contact surface area, & the base explosive's physical structure all contribute to the efficiency of the cap.

In commercial production, special attention is often paid to the cap's housing. Anodized aluminum is often used and the type of aluminum is often not the soft, common Al tubing. What is produced by many firms are caps which use a type an extremely hard aluminum which does not "bulge" during the nano-seconds of a detonation, but shatters. This contained energy & violent release increases efficiency. The anodizing halts further oxidation.
The type of aluminum used is not easy to come by: but a source does exist. Aluminum arrows (used in archery) are made of the same tubing material and are unusually brittle. They are very strong in a linear fashion but shatter when used as a cap housing. They are very consistent & are generally the closest one can get to commercial cap bodies. When compared side by side with common 60x series aluminum tubing the simple substitution of this type of tubing appears to result in a much more profound detonation.

edit:
I have seen side by side comparisons that convince me of the above. Additionally I have no doubt that one tenth of a gram of lead azide is as much as would be needed in most instances as initiation has gone far, far below that.



[Edited on 27-7-2010 by quicksilver]




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[*] posted on 27-7-2010 at 07:21


If everything was in fact perfectly optimized and cutting edge then you are probably right. Cutting edge is not where I am at, and I am more interested in more common practical things. I find Picric Acid to have a very nasty tendancy to go low order detonation, if not overdriven quite a bit. A bit different perhaps, but I was just lately reading an old popular science magazine article about Guncotton(from around 1900), and it said that the navy scientists found that dry compressed Guncotton could be initiated (if under perfectly optimized conditions) with a mere 2.7 grains(~0.175g) of Mercury Fulminate. In actually practice however they found it most practical, all things considered to use something like 35grains(~2.27g) Mercury Fulminate. This is without doubt a huge excess. It does seem to show that they were thinking along the same lines as Rosco though.

edit: BTW what is the diameter of these arrows, I don't think going smaller than 5/16" would be advisable with TNP. I actually prefer to use around 3/8", but I could be going overboard on the diameter. It (TNP) has a fairly large critical diameter, probably even larger in an improvized scenario.

[Edited on 27-7-2010 by Hennig Brand]
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[*] posted on 27-7-2010 at 07:27


Quote: Originally posted by Hennig Brand  
I find Picric Acid to have a very nasty tendancy to go low order detonation, if not overdriven quite a bit.


?
Now I've heard of NC doing this but not of Picric Acid. I am intrigued. What happen to show a low order det? Are you speaking of a cap det or a volume detonation?
Mercury fulminate is annoying to work with as it seems to demand high density to detonate with any real authority.
{OT}
I would really like to get a digital microscope camera. Some time back I was using a microscope to determine if any needles existed within lead azide samples (which IS a damn good idea from a safety standpoint). & I happen to check the classic and "optimized" clathrates at 400x - & at that magnification, you can see the lattice.



The nice thing about using arrow aluminum is that the sizes range significantly and actually available up to close to .5"
I was quite impressed with using that material. The level of quality is profoundly high. The interior in anodized as well as the exterior, it can be cut with little problem. The "shattering element" is no joke however. they splinter in such a manner that you really do not want to experiment without so genuine distance or shielding. But if two designs are placed one after the other, the "arrow aluminum" will show a performance that the softer material will not; with a variety of explosives.





[Edited on 27-7-2010 by quicksilver]




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[*] posted on 27-7-2010 at 07:52


I have seen it a few times now with my own experiment, where I got a definate detonation but it did less than half the damage to the rock, or steel I had it placed on than it did with a bit more initiation. I have also seen it described a few times at least in old military/explosives books, IIRC it was one of the major criticisms of TNP shells, I think TNT also has this problem to some extent. From what I read the German shells (TNP) were particularly bad for going low order or underperforming, but it was a trade off between that and higher sensitivety(more primary, etc). Apparently when close to the critical amount needed(maybe not even all that close) it was often anyones guess whether it would go high order or low order. This is just from stuff I have read, I hope I am not just repeating someone elses bad opinions.

If I come across some references I will get back to you.

In my own experience it definately needs to be overdriven, whereas something like ErTeN(ETN) always seems to work well I find(maybe I just always load it lots heavy, it is kind of sensitive).

A microsope camera would be very neat indeed. You could post some very interesting pictures for sure.

edit#2(revisit):The low order det may be more to do with caps and boosters, I don't know. The Germans did use alot of Picric Acid boosters, they often lacked "authority" quite often that is for sure, from what the old sources say. Maybe with a large volume of TNP it wouldn't be as much of a problem, and it would pick up to a high order, even if started out low order.

edit:The arrows sound really good actually, thanks for pointing that out:)

[Edited on 27-7-2010 by Hennig Brand]

[Edited on 27-7-2010 by Hennig Brand]
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[*] posted on 27-7-2010 at 07:54


Quote: Originally posted by Hennig Brand  
Just for fun, here is an old barrel I found and put to good use. I like to call this photo "Barrel Blasting".



You could cobble together a lead block for Trauzl's Lead Block
Test.
I could make you one, however, and 8x8" cylinder of lead
me thinks would be expensive to ship.

http://tinyurl.com/2eto3cu

A Ballistic Pendulum perhaps.

"This apparatus consists of two essential parts, a cannon in which
the charge is fired and a pendulum which receives the impact of
the products of combustion and of the stemming. The pendulum is
a 12.2-inch United States mortar, weighing 31,600 pounds, which
is suspended by means of a stirrup from two cast-steel saddles
fitting over a steel supporting beam that rests on nickel-steel knife
edges on steel bearing-plates supported by concrete piers. The
swing of the mortar when the cannon is discharged into it is
measured by an automatic recording device and is taken as a
measure of the propulsive effect of the explosive."

http://tinyurl.com/3xhqkks pg. 47



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[*] posted on 27-7-2010 at 08:26


Your Lead cylinder would weigh about 65lbs if I didn't mess up somewhere. A little heavy for shipping, you are correct.

Your ideas sound good, I kind of like the idea of the witness plates simplicity and cheapness, but I definately should rig something up much better than an old surface rusted barrel. Nevertheless the barrel did teach me a few things that I wouldn't have known otherwise.

I could maybe rig up some kind of mortar and ballistic pendulum, for making comparisons. I have made a couple of black powder cannons now (fairly crude though), so am used to working with metal a bit. A friend and I made a 3.5 inch(350 caliber?) black powder cannon just last year(large piece of heavy seamless pipe to start), finding good(cheap) projectiles was/is the hard part. Back on topic, I like the idea of the Ballistic Pendulum, sounds interesting.

[Edited on 27-7-2010 by Hennig Brand]
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[*] posted on 27-7-2010 at 09:29


This is fine and dandy if you have large amounts of scrap material laying around. But if you want to see performance from a cheap stand point, use the sand test.
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[*] posted on 27-7-2010 at 11:17


Quote: Originally posted by pjig  
This is fine and dandy if you have large amounts of scrap material laying around. But if you want to see performance from a cheap stand point, use the sand test.


As dobe noted the sand test measures brisance [Please!
The word is French and not pronounced as spelled. Don't
look like an amateur by pronouncing it bris - ance.]


This from PATR 2700, Volume 1 XXI & ff, which see for drawing.

Sand Test or Sand Crushing Test (Sandprobe, in Ger) (Essai au sable, in Fr)
(Prueba de la arena, in Span).

This test, devised by W.O.Snelling in 1910 and studied extensively
by C.G.Storm & W.C.Cope (Ref 1), is considered to measure the
shattering (disruptive) power of an expl, called brisance.* This
characteristic is im¬portant because it determines the
effectiveness with which an expI can fragment a shell, bomb
casing, gren¬ade or warhead of a rocket

The sand test consists essentially in detg the amt of standard
sand (supplied by the Ottawa Silica Co, Ottawa, Ill), crushed by a
std wt (usually 0.400 g) of expl. The original sand passes through
No 20 mesh sieve(US Std) and contains no particles smaller than
No 30 mesh. The test in conducted in a cylindrical steel bomb, 3
1/2 " in diam, 8 1/2 " with cylindrical cavity 1 1/2" diarn and 6"
deep. Procedure: Transfer an accurately weighed 0.400 g portion
of test expl, of such granulation as to pass through a No 100 sieve,
to each of five empty No 6 commercial blasting cap shells (of Cu,
Al or gilding metal) held during transfer in loading block. Insert in
each shell a reinforcing cap provided with a small hole in the
center and by means of a plunger subject the charge(previously
placing it behind barricade) to a pressure of 3000 Psi for 3 mins.
With a pin, prick the powder train in one end of a piece miner's
black powder fuse 8-9" long and crimp to the pricked end one of
the above loaded No 6 caps, taking care that the fuse is held
firmly against the charge in the cap. Pour into the bomb 80.0 ±0.1
g of std sand and level it by striking the bomb with a hammer.
Lower the cap into the bomb so that the car is centered at the axis
of the bomb And just touches the sand. Pour 120 +/- 0.1 g of
sand being careful not to disturb the position of the cap. Pass the
upper end of the fuse through a tightly fitting rub¬ber tubing
which is then inserted in the hole of the bomb cover. Lower the
cover into position and fasten it securely by means of two bolts
with nuts. ignite the fuse and after expln of chge, remove the
cover. Transfer the contents of the bomb to a piece of glazed
paper, cleaning the bomb and cover thoroughly. After removing
pieces of cap and burnt fuse, transfer the sand to a No 30 sieve
fitted with a bottom pan and a cover and shake for 3 mins on a
mechanical shaker. Weigh to 0.1 g the sand which passed through
the sieve and record the average of all five values. This wt is the
sand test value or brisance value.


If the expl chge cannot be initiated by flame, it is pressed without
insertion of the reinforcing cap. Then a 0.300 g chge of LA is
placed on top of the expl, followed by the reinforcing cap and
another compression at 3000 psi. Then the fuse is inserted and the
chge initiated as above. After detg the amt of sand crushed by
these caps, subtract the wt of sand crushed by 0.300 g LA, when
loaded alone in No 6 caps

A modification of this test applicable to liquid expis is
described in Ref 9, pp 9 & 11. The sand test may also be applied
to detg the amt of LA and/or tetryl, that must be used as initiator
or booster to insure that the sample crushes the max net wt of
sand. This is designated as sensitivity to initiation test. (See also
Ini¬tiating Efficiency of Primary Explosives by Sand Test.) Refs:
I)US BurMinesTechPaper 125(1916) 2)US BurMines Rl 2558(1923)
2a)H.Kast & A.Haid, SS 18, 166(1924) DUS BurMines RI
3039(1930) 4)US BurMinesBull 346, (1930,109 13 5) L.V.Clark,
IEC 25, 664 & 1387(1933)6) OSRD Repts 803 & 804 (1942),24 7 7)
Davis(1943),422 3 8)Perez Ara (1945),124 9) PATR 1401,Rev
1(1950),7 12 9)TM 9 1910 (1955),60 10) PATR 1740,Rev 1(1958)

Send Test for Detonators. See initiating Efficiency of Detonators by
Miniature Cartridge Test and also under Initiating Efficiency of
Primary Explosives by Sand Test

*According to W.R.Tomlinson, Jr, formerly of PicArsD sand test
det "energy' I rather than brisance.


200 Gram Sand Test
TNT at 48 Grams = 100% you can do the math.
[Veltx No. 448 = 138% TNT]

[Ballistic Mortar and Trauzl TNT = 100%
Except PLX 95/5 where the Trauzl value uses
PA as 100%]

Amatol 80/20 ........................ 35.5 ...BM 130 Trauzl 123
.......60/40 .........................42.5 ...BM 128
.......50/50 .........................42.5 ...BM 124
Ammonal (AN 22 TNT 67 Al 11) .........47.8 ...BM 122
Ammonium nitrate ......................nil ...BM 56
Ammonium perchlorate ..................6.0
Baratol ..............................26.8
Baranol ..............................39.8 ...BM 96
Black powder ..........................8 .....BM 50 Trauzl 10
BTTN (liquid) ........................48.6
Composition A-3 ......................51.5 ...BM 135
............B ........................54.0 ...BM 133 Trauzl 130
............C ........................46.5 ...BM 120
............C2 .......................47.5 ...BM 126
............C3 .......................53.1 ...BM 126 Trauzl 117
............C4 .......................55.7 ...BM 130
Copper chlorotetrazole ...............27.4
Cyanuric tyriazide ...................32.2
Cyclonite (RDX) ......................60.2 ...BM 150 Trauzl 135
Cyclotol
.........75/25 .......................____
.........70/30 .......................56.6 ...BM 135 ...BM 135
.........65/35 .......................55.4... BM 134 ...BM 134
.........60/40 .......................54.6 ...BM 133 ...BM 133
Cyclotrimethylene trinitrosamine .....59.2 ...BM 130 ...BM 130
DBX .................................146 .....BM 146 ...BM 146
DATNB ............................... 46.6 ...BM 100 ...BM 100
Diazondinitrophenol ..................47.5 ...BM 97 ....BM 97
DEGN (liquid) ........................42.2 ...BM 90 Trauzl ... 77
DNPF
DNPS
DNPTB
DNT ..................................19.3 ...BM...71 Trauzl 64
DPEHN ................................57.4 ...BM.142 Trauzl 128
LVD (Mil Low Velocity Dynamite) ......40.5 ...BM ...92
MVD ..................................52.6 ...BM ...122
EC Blank fire (Smokless powder) ......46.8
Ednatol 55/45 ........................49.4 ...BM 119 Trauzl 120
GTNB
Explosive D ..........................39.5 ...BM 99
GLTN (Liquid) ........................13.1
GDN (Liquid)
H-6 ..................................49.5 ...BM 135
Haleite ..............................52.3 ...BM 139 Trauzl 122
HBX-1 ................................48.1 ...BM 133
HBX-3 ................................44.9 ...BM 111
HEX-24 ...............................12.5
HEX-48 ...............................23.7
HNO ..................................52.1
beta-HMX .............................60.4 ...BM 150 Trauzl 145
HTA-3 ................................61.3 ...BM 120
Lead azide ...........................19.0 ...BM ___ Trauzl 39
LDNR .................................20
LDNR Basic ...........................15
Lead Styphnate .......................24 ....BM ___ Trauzl 40
Mannitol Hexanitrate .................68.5 ...BM ___ Trauzl 172
Mercuy Fulminate .....................23.4 ...BM ___ Trauzl 51
MTN (Liquid) .........................43.7 ...BM 136 Trauzl 140
Minol-2 ..............................____ ...BM 143 Trauzl 165
MOX-1 ................................10.6
MOX-2B ...............................11.5
MOX-3B ...............................33.2
MOX-4B ...............................33.6
MOX-6B ...............................10.8
Nitrocellulose 12.6% N ...............45.0
...............14.14% N ..............52.3
Nitroglycerin (Liquid) ...............51.5 ...BM 140 Trauzl 181
Nitroguanidine .......................36.0 ...BM 104 Trauzl 101
NIBTN (Liquid) .......................28
NSX ..................................39.5
Octol 70/30 ..........................58.4 ...BM 115
......75/25 ..........................62.1 ...BM 116
PB-RDX
PETRIN
Pentolite 50/50 ......................55.6 ...BM 126 Trauzl 122
..........10/90 ......................49.5
PETN .................................62.7 ...BM 145 Trauzl 173
TNA ..................................48.1 ...BM 100 Trauzl 107
Picratol .............................45.0 ...BM 100
Picric Acid ..........................48.5 ...BM 112 Trauzl 101
PIPE .................................41.6
Plumatol .............................32.4
PLX (Liquid) ..........................8.1
........95/5 ........50.6 ...BM 134 Trauzl *PA* .............................................................127
KDNBF .................................44.8
PT.....................................54.8 ...BM 132
PTX-2 .................................56.9 ...BM 138
PVA-4 .................................58.5
PVN ...................................49.9
RIPE ..................................40.1 ...BM 118
Silver Azide ..........................18.9 ...BM ___ Trauzl 88
Tetracene .............................28.0 ...BM ___ Trauzl 61
TNC ...................................41.3
TNO ...................................16.3
Tetryl ................................54.2 ...BM 130 Trauzl 125
Tetrytol 80/20 ........................54.0
........75/25 .........................53.7 ...BM 122
........70/30 .........................53.2 ...BM 120
........65/35 .........................52.6
TNT ...................................48.0 ...BM 100 Trauzl 100
Torpex ................................59.5 ...BM 138 Trauzl 164
TATNB .................................42.9
TEGN (Liquid) .........................14.7
Trimonite .............................44.2
TNETB .................................____ ...BM 136
Trinnitro Triazidobenzene .............____ ...BM __ Trauzl 90
TPEON .................................58.9
Tritonal 80/20 ........................____ ...BM 124 Trauzl 125
Veltex No. 448 ........................66.4





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quicksilver
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[*] posted on 27-7-2010 at 12:21


Frankly, I once attempted making a friction Pendulum apparatus & .....it wasn't my best work.
The real problem is that as contact surface increases so does friction input; to make sure one's sample receives contact that area needs to be about a square centimeter. But build up that contact space and the results are thrown.
I saw a few picture of devices used by the USBoM, another from a private "powder company", etc. They simply don't get close enough to see how they solve that contact area problem.

The Trauzl blocks I have seen appeared to be 1Kg as a 4"x4" cube with a 6mm hole. I hefted it and it seemed like 2lbs +. However I once saw a picture of one with a larger hole (it did appear 4x4 however). The lead should be pure; if it has tin or other elements the results will be thrown off & I don't know if it will expand without tearing or fragmenting. Making a mold for one would be pretty simple with 5 plates, some "C" clamps, and some "mold release" from hand swedging home-made bullets.

An impact test would be the easiest. A track for a weight (it's also been 1Kg TTBoMK) to slide down - could be rigged up pretty easily; the only challenge would be the actual impact surface....Too small or too spread out & you tweak the results. There would need to be one standardized contact surface area & I have not read what that is exactly. Pictures do not come close enough to the base area to make a determination.



edit:

Wizard - if you ever get any info on the above I would seriously appreciate it. I have not found contact surface area (size) for impact testing nor have I found contact design for friction (I have found that it was one cm however). I checked U.S. Bureau of Mines, Weaver, Federoff, Urbanski,etc (the usual).



[Edited on 27-7-2010 by quicksilver]




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[*] posted on 27-7-2010 at 13:51


Quote: Originally posted by Hennig Brand  
I A bit different perhaps, but I was just lately reading an old popular science magazine article about Guncotton(from around 1900), and it said that the navy scientists found that dry compressed Guncotton could be initiated (if under perfectly optimized conditions) with a mere 2.7 grains(~0.175g) of Mercury Fulminate. In actually practice however they found it most practical, all things considered to use something like 35grains(~2.27g) Mercury Fulminate. This is without doubt a huge excess. It does seem to show that they were thinking along the same lines as Rosco though.




"Wet gun cotton is not affected by percussion and can be
detonated only by the detonation of an amount of dry
guncotton bearing a certain ratio to the weight of wet
gun cotton employed. Its explosive effect is much greater
than that of dry gun cotton."

Compressed Gun Cotton for Military Use.
Translated from the German of Max von Föster
With An Introduction on Modern Gun Cotton
Its Manufacture, Properties and Analysis
By Lieut. John P. Wisser U.S.A.
New York: Van Nostrand, Publisher
1886


And I expect other refs. And Good-grief - another book I
own that is now available @ google.com/books!

Byda Them Brits used compressed gun cotton in WW II for demolition charges.
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