Frustrating Failures

[spydamonkee]

ok here is the deal... FGAN is damn frustrating, as i have had numerous misfires, failures & partial detonations, ill attempt to list them below with what i think caused them to fail.

The FGAN (Fertilizer Grade AN) i am using is 27-0-0-0 called Calcium Ammonium Nitrate in prilled form & all my APAN ratios are about 10% and FO - AN 5 - 6%.

1.
First ANFO attempt - Failure - Not Recorded:
5kg's of CANFO 4.750kg prilled CAN, 250g desiel, contained in plastic paint bucket buried 3 feet deep with a film canister (FC) of APAN as booster.
Result = Complete failure, no white smoke, heaps of white prills everywhere.

Reasons & Possible Solutions?:
Desiel was not absorbed by CAN because of calcium coating thus was not sensitized, maybe the desiel should have been left for a few days instead of hours to have a chance of soaking in?... booster too small in contrast to main charge.

2.
Second ANFO Attempt - Partial Detonation - Recorded on Video:
This attempt was captured on video click the link in my signature and view 'ANFO 1kg - Flaxbush.mpg' also check out this <a href="http://www.roguesci.org/ubb/ultimatebb.php?ubb=get_topic;f=12;t=000022" target="_blank">thread</a> for more info
300g recrystalized + about* 650g Crushed CAN mixed with about* 60g desiel contained in plastic bottle about 6" * 11" buried 1m down and 1m into the bank with 150g APAN as booster.
Result = Partial Detonation with lots of white smoke a 'dull' thud being heard and about two wheel barrows full of dirt, clay & sand being moved & the flaxbush was shaken about from the blast, undetonated CAN prills were found in the shothole.

Reasons & Possible Solutions?:
I have no doubt that it was only the 300 grams or so of Recrystalised AN (rAN) that detonated the and the rest was scattered & compressed against the walls of the container and crater, maybe a few hours is not enuff time for CAN even when crushed to absorb the fuel effiecently?

3.
Third ANFO Attempt - Partial Detonation - Recorded on Video:
Video not converted & uploaded yet.
500g CANFO, 475 grams CAN crushed & some powdered, 25 grams desiel contained in a steel tin buried 1 foot deep into clay with a sizable rock sitting on top of stemming, FC of APAN as booster.
Result = Partial Detonation, lots of white smoke deep thud fist sized chunks of clay flying everywhere aswell as the rock being thrown a fair distance missing the camera by 1m or so, smooth crater in the clay about a foot deep and 1.5 feet across... not really that much bigger than the FC booster makes in the clay :(

Reasons & Possible Solutions?:
again i think it is because of the calcium coating hindering the absorbtion of the fuel as only a hour or so was allowed for it to soak in and not all the prills were crushed also the small size of the charge and booster made me not worry too much about this charge, there was alot of white remains left in the crater so less than half went off. i will be trying this method again when i get a better method of making sure all the prills are crushed enuff for the desiel to soak in.. IE not powdered but basically just crushed enuff to crack the coating on the prills.

4.
Fourth ANFO Attempt - Mostly Failure - Recorded on Video
Video not converted & uploaded yet.
2kg ANFO, 1.9kg rAN, 100g desiel 2 hour soak time, conatined in steel tin buried 4 feet deep, 25g FC APAN booster.
Results = Mostly Failure dull thud heard, small amount of debree fired out of the shot hole, bottom of shot hole enlarged with some white smoke pouring outa the hole, alot of white remains stuck to the sides of the shothole and container, waste of a days work of recrystalising :(

Reasons & Possible solutions:
main reason i think is the density of my ANFO was too high as everything else was within the limits that i know about ANFO, the rAN was dry and felt, looked and handled like cocanut mix, i was carefull to try not to compress the ANFO upon loading into the container which was done on site to avoid settling from the trip to the blasting site, however when i put the lid on the container i may have compressed the ANFO a little bit which may have been enuff to kill all the air spaces needed to give ANFO 'hotspots' and give the booster shockwave a looser mass to travel thru. well ANFO has mainly just frustrated me so far so i will be trying rAN mixed with these water softner resins i have aquired that are small balls less than 1mm across so hopefully that should give me the required hotspots, i will also be trying crushed CAN again... all these charges will be tryed with decent charges of 1kg or more :D

well i hope this helps any of you out there who have been having as much problems as i have had ... now you know what NOT to do :D
if anyone would be able to give me some advice on how to make use of my 40kg bag of FGAN 27-0-0-0 CAN it would be most apreciated.

I certanly wont be giving up on ANFO but ill take a break and try my hands @ ANNM as i am buying 1ltr or so soon @ 27 dollars nz a ltr FFS!

*Kitchen scales not very accurate about 50g resolution, i know have 2g resolution digitals now
**if any mods thinks all this info is not worthy of its own thread i owuld rather have this topic deleted than my account :p , i have searched the forum, its archives & the net up and down for ways to detonate ANFO and i was thinking this info could help others as my next ANFO charges WILL go off <img border="0" title="" alt="[Wink]" src="wink.gif" />

[Anthony]

$27NZ/litre is a good price.

First of all, I'd try some ANNM using the fertilizer you have, that should be sensitive to a gram of AP or HMTD.

Then I'd make up two bean can sized ANNM charges, on as a control and one put into a bucket with a few kilos on your ANFO. Bury both and compare the amount of earth shifted/crater size, or place on the surface against a target, which you can asses the damage afflicted on, like a brick wall.

If your ANFO is made with crushed prills or had the coating washed off, then I think your booster is the weak link. ANNM will give the ANFO a sharper slap than a peroxide, not to mention being safer to handle. It's apparently quite common for commerical blasters working with ANFO, to use a half stick of high percentage dynamite as a booster. That's 1/4lb of bristant explosive.

[NoltaiR]

Peronsonnaly my most frustrating failures have come with the making of picric acid. I use the H2SO4 method (and in large amounts too)... I have only attempted it twice but the materials and time that I wasted in doing so was enough to keep me from ever trying it again. I mean, with the amount of H2SO4 and KNO3 that I wasted on those two tries I could have made quite a bit of HNO3 which would have been much more useful anyways.

[0EZ0]

I have to ask, what made you buy the Calcium coated AN?
Using it straight without purifying would be an absolute bitch.

My suggestion, if you plan on making such large charges with the AN, then go buy yourself another type of Fertiliser Grade AN. Because purifying alot of Calcium AN is going to be quite alot of work, and probably not worth the effort.

You could use your remaining Calcium coated AN for smaller charges. But don't forget to purify.

When looking for FGAN, make sure it is to the most pure specifications, and do take the time to find multiple places of purchase. Look for the least amount of addatives. Don't be afraid to ask questions, because you might regret having bought 25/50 kilos of AN that is almost useless for explosive purposes.

Also make sure you've got an excuse at the ready when buying it. 'I would like to purchase some Nitrate fertilizer for my lawn, as it is not in the greatest shape at present' <img border="0" title="" alt="[Wink]" src="wink.gif" /> , 'I have a home tobacco crop, and it has come to my understanding that Ammonium Nitrate has quite a positive effect on tobacco's growth', etc. yada yada, bla bla.

Hope it helps..

<small>[ September 08, 2002, 10:33 PM: Message edited by: 0EZ0 ]</small>

[spydamonkee]

well it is the only source of bulk AN i have found locally so far so i purchased it , was only 30$ for 50kg bag thats like $15USD, only other AN i have found so far is 100% cold pack stuff :D
recrystalising the AN aint that hard just time ocnsuming and messy, i could can recrystalise 5kg in one day :D (i think im gonna hate this months power bill)

few days then ill try a ANNM charge using 2 grams AP as BC
well thanks for the help i'll let ya'll know how i get on.

[DBSP]

All your charges are under-primed. Expecting a stubborn ANFO charge that hasn't been allowed to soak more than an hour to fully detonate isn't something that will happen.

The ANNM will definately help you a great deal. I have one suggestion that might help you. Purify a couple of kilos of AN the way I have described in "cap sensitive mixtures in KIFE" thus you get a relatively sensitive charge. Lets say you wan't to prepare 2000g charge, start with your normal ANFO (1700g) and put it in the container first then add the sensitive density lowered ANFO (300g) on top of that and stir it arround so that some of the normal ANFO gets mixed with the sensitive one, prime it with 50g of ANNM. It would probably make it a bit more easier to detonate.

BTW does you AN have the calcium additive mixed through out the hole prill or is it one coated with it?

[spydamonkee]

i think the calcium is just in the form of a coating on the prills, im unsure as to weather it is mixed into the prills or not and do not know how i owuld be able to tell.

anyone able to tell me what those small brown things are in almost all bulk fertilizers?

cheers for the info DBSP i'll try your method sometime.

[KinePak]

OK, the main problem I see is you arent using a big enough booster charge, u need an explosive that exerts extreme pressure at intitial detonation to send a large enough shockwave through the coating and into the AN. Thats been my experience with the stuff, b/c I had no problem setting off that 50lb bag, but see if you can get some 34-0-0 fertilizer thats what I use, but I am also using Kinepak as my booster which is 100% powdered AN, and 100% nitromethane.

[simply RED]

1. In every manual it is said that 200g TNT booster is required to blow up 6%ANFO. I've blown up 4%ANFO with 500g APAN with 20%CTAP. Making this is insane, so, nitroglycerine booster will be needed if you want to make 6%ANFO, about 100g NG-NC mix.
2. Watch out for the density, it must be 0,6-0,9 g/cm3! Mill all the AN prills, and use CLEAR ammonium nitrate fertilizer grade, NO CALCIUM NITRATE! Use a machine for milling korn(and other foods for animals for quantities more than 10kg).
3. Use formulations with Al powder. I've made a mix: 6%-7% bronze paint, 94% AN(THE BEST FORMULA!!!). The bronze paint is sold in every hardware store! This mix is detonatable with 20g CTAP, i detonated 2,5kg of it with 50g NG,NC(90%NG) and N8 commercial cap. Use the mix immediately after preparation, cause the paint is volatile...
4. Chose propper container, all my charges were tested above ground, no misfires were observed, except in one, where the prills weren't crushed.
5. Chose propper ELECTRIC firing system! The homemade fuses are very unpractical and hazardous, once, 1kg charge blew up 7 meters from me, because the fuse was bad...

It was a method for making ammonites from an prills, which involved soaking the prills in water, then heating and evaporating, when i tried it, i tested 250 grams charge of AN, bronze paint 6% paint. Density was 0,6. Fired with N8 cap with 5 grams clear NG in a test tube, it gived perfect full detonation.

[Al Koholic]

Yah...using a big booster in ANFO charges is a must! I have detonated hundereds of pounds of ANFO before (70 lbs was the biggest single shot) and each time I used a blasting cap of lead azide with a lead styphnate coating. The booster charge was a 50/50 mix of cast TNT and PETN. I believe this is called pentolite. Either way the booster was about 150 grams...about the size of a fist give or take. It was an extremely effective booster so I would recommend going to ANNM as well.

Just my 2 cents...
al

Also...crushed (powdered) AN will be harder to set off than a mix which employs good quality (ie: unmixed density of about.85) porous prills.

<small>[ September 09, 2002, 12:15 PM: Message edited by: Al Koholic ]</small>

[simply RED]

Crushed AN is most sensitive.
Did you made the booster?

[a_bab]

I've seen a documentary on Discovery channel about AN and how the government tryed to render it useless (somehow) for exploding purposes. The result was null; there is no possibility to coat the AN prills with something so it'll be undetonable IF you use the proper booster.
I would crush the AN because in this way the calcium carbonate or WTF they are using as coating will not be a problem for detonation.

simply RED, please e-mail me.

[Jumala]

If I read it right you tryed to detonate kalk-ammon-saltpeter fertlizer 27-0-0.
This is a waist of time, material and money.
This fertilizer is a mix from AN and ground kalk-stone(sand) and it is made to prevent it from use as explosive. And the sand does a good job in this matter.
Your only possibility is to remove the powdered stone or to buy 34-0-0 fertilizer.

You can do it economical at this way.
(I will load pics of the yield to the FTP upload folder)

At first heat up 5 liter or more water in a large high pot.
Then poor in so much (3-5l or more if possible) kalk-ammonsalpeter and stir untill you think that nothing more can be dissolved.
Don´t use to less fertilizer. Hot water can dissolve a shitload of AN.
After this is done shut off the heatsource and let it stand still for 2-3 hours.
It is surprisingly not nessesary to hold the solution hot. It takes some more hours before the crystalls start growing.
Now most of the mud has settled down on the bottom. Remove the muddy foam from the solutions surface. (Spoon)
Then use a flexible tube to drain the warm solution in an other large pot or a bucket at a lower place. (Don´t suck off the mud also)

It is impossible to filter the solution because the mudd kills every filter.

When the mud is cold some large but dirty AN crystals appear in the rest solution. Collect them for the next batch.

You can now filter this solution through a coffee filter to remove the last fine mud but I think it isn´t nessesary.

Now let the solution cool down to roomtemperature and wait some hours untill a day for the crystals. The size of the crystals you will get depends on how fast the solution cools down. Fast cooling gives a big bunch of needles. Slow cooling gives crystals like pencils with a size that is limited only by the diameter of the pot.
When no more crystals appear suck of the now very clear solution in an other bowl and let the crystals dry.

Put the clear solution in the fridge and you get a second, very clean bunch of crystals.

It is interesting to see that nearby nothing of the mud settles in the AN crystals. The crystals are clear and white.

At last give the rest solution back in the first (cleaned) pot, poor in the dirty AN (out of the mud) and start the proceed again.

While making my first batch I waited a day for the crystals but nothing happens. I have poored to less fertilizer in the solution so I must do the procedure again.
The crystals are containing a lot of water and they lost some of their volume while drying in an oven and they decompose to a white crystal powder.

The more saturated the solution is the more time is nessesary to settle down the fine mud.
It takes 24-48 hours or more to get a clear solution. Put the clear solution in the fridge and you get best quality AN crystals.
Dirty crystals, growed in the muddy solution, can be purified in the next batch.

[spydamonkee]

well i have had no problems using this FGAN for APAN mixes i just powder it out of the bag then mix with AP, goes off fine
well i'll be doing alot mre testing with ANFO untill i find a way to do it cheaply and simply

when i recrystalize my FGAN i just dissolve as much FGAN in hot water as i can then i let it settle for about 15 mins then i drain off the solution leaving the thick sandy whitish mud behind, i then boil the solution down so onyl a small amount of water is left then i chuck it in the oven for a while and i end up with a baking dish full of crystals, usually 1kg or so.

the recrystalized stuff makes my APAN charges really powerfull compared to the stuff powdered right outa the bag.

[spydamonkee]

ok i have had a few more failures recently, however not with ANFO but with ANNM, my first test of ANNM was 200g recrystalised AN mixed with 50ml's or NM, contained in a plastic baggy with a 308 shell filled with AP as a det, det was simple taped to the bag which was placed on the ground with a small rock on top.
this chargbe detonated nicely with a very loud report and blew the rock to smithereens :D

however my last 3 tests of ANNM have all failed

2 failed because i was using powdered CAN not recrystalised AN (ANr) but the other failed and im not sure why... as it consisted of 200g ANr and 50g (aobut 40ml or so) NM, the problem was the det i think as this time i only used about 1g AP in a drinking straw, charge was placed the same way my first was.

?? does ANNM need a certain density like ANFO or does it not matter as much, also what is the best ratio of AN to NM to use as from my searching of the forums and the web i have seen many different ratios all claiming to be the best, my charge that detonated used 80 - 20 (AN by weight NM by ml's)

[Helos]

Hello!
I always (one time) use the ratio 25%NM 75%AN and it is powefull and sensitive for inittiation, The stocihometrich proportions is 66,6 /33,3 But then you have to use more NM, and also the AN, cant always suck up that much. Even better are the mix with methanole 3,3%methanol, 15,6 % NM, and AN, (I may have forgot the exakt numbers here :(, look around! )

I think that the best is to tamp ANNM as hard as possible, but dont forget, it can be stone hard, and you det dont fit in it <img border="0" title="" alt="[Eek!]" src="eek.gif" />

[Helos]

I once tried to detonate a big quantity of 27,6-0-0 also 2,3 %mg ions and I dont now the rest, called N-28
I used 5 % motor oil, next time diesel!
I used as much as 6kg! I used a booster at 700g ANNM!
I think it detonated, it did an enormos damage to a huge tree, root blown up, but it still standed high! The sound was impressive, no residues of fertilizer were found. Next time I will compare it with booster only, but I think that this one detonated :)

[Anthony]

With ANNM, I have always used 25% NM, but by weight, not volume. The AN is out-of-the-bag FGAN, powdered and dried. I found that the NM would not properly penetrate the AN prills, and gave a very weak, partial detonation.

Density wise, I'd avoid compressing at all, as it lowers sensitivity. Might be worth experimenting with higher densities later on, but when you just want to get it working, you need maximum sensitivity.

I shake up the charge, insert the det, then give it another quick shake to loosen the ANNM compressed around the det when it was pushed in.

Haven't had a failure with 1gm of AP yet :)

[spydamonkee]

so helos when you detonated your 6kg how did u prepare your FGAN, did u just use it straight outa the bag prilled, and how long did u leave it to soak up the FO etc.
im gonna use 500g ANNM as the booster for a 5kg ANFO charge and i wanna make sure this one will work :/

[xoo1246]

In my oppinion N28 will not work for ANFO. You will have to purifiy or use a better product.

Helos: How was the charge place, in contact with a tree? Dug down? Diameter of tree? Did you find any residue? How large was the crater?