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jclarkdawe
10-15-2014, 04:16 PM
Bad guys are using NITROUT from Russia. Two questions:

1) With about 450 kilos or 1,000 pounds of NITROUT, what would be the blast range. How far away can I put another 450 kilos and be safe from the explosion setting it off.

2) For bonus question, what size carton (height x length x width) and weight carton would this be shipped in?

Any help will be rewarded with rep points.

Best of luck,

Jim Clark-Dawe

Bolero
10-15-2014, 08:14 PM
On flat land in the open, or in a built up area?

At ground level, or above ground level?

Don't know much, but do know that in general buildings can block a blast wave or concentrate it into an area by channelling say down an alley or reflections from the front of a building.

An explosion is a bit like sound in the sense that it is a compression wave that is affected by solid surfaces.

Further thought arising from the sensitivity of nitroglycerine - do you know what level of "jolt" the explosive you mention needs? As in would a sonic boom trigger it?

So, more questions than answers, but hope they help. :)

jclarkdawe
10-15-2014, 09:12 PM
On flat land in the open, or in a built up area? Forested.

At ground level, or above ground level? About 30 feet off the ground.

Don't know much, but do know that in general buildings can block a blast wave or concentrate it into an area by channelling say down an alley or reflections from the front of a building. Blast zone is always a scientific wild ass guess.

An explosion is a bit like sound in the sense that it is a compression wave that is affected by solid surfaces.

Further thought arising from the sensitivity of nitroglycerine - do you know what level of "jolt" the explosive you mention needs? As in would a sonic boom trigger it? NITROUT is Russia's version of C-4 and Semtex. I'm assuming it's as stable as either of those products. It should be able to survive a reasonable jolt.

So, more questions than answers, but hope they help. :)

Thanks for the questions to clarify the issue.

Best of luck,

Jim Clark-Dawe

badwolf.usmc
10-15-2014, 09:53 PM
How much detail do you want? Better yet, what are you trying to do?

(I'm a 1371 in the Marines, working with explosives is what i do.)

jclarkdawe
10-15-2014, 11:40 PM
I'm trying to make sure that the second pile of explosives doesn't explode when the first goes. Or how far away you need to set the second pile to be safe from the first one exploding. My guess is if I set the two piles about 500 feet apart, I'm okay, but I'm not sure. And large amounts of explosives don't give a good blast range.

All the explosion is going to do is blow up some trees, so its strength at blowing something up is not the issue, it's the safety zone.

If I have the details on the box, the scene where the guy has to unload it becomes better, but it's not that big an issue, as not that many people would know if I get it wrong.

Best of luck,

Jim Clark-Dawe

ironmikezero
10-16-2014, 12:35 AM
Jim, I'm sure badwolf,usmc will explain better than me, but I can share this (per BATF & US Army Corps of Engineers... 450Kg/1,000# in a vehicle trunk)...

Lethal air blast - 125'/38m

Minimum evacuation distance - 1,750'/534m

Structural damage/falling glass hazard - within 1,750'/534m

There's a difference between high and low explosives (detonation vs burning). NITROUT, like C-4, PETN, Semtex, etc., is considered a high explosive. In contrast, ammonium nitrate & fuel oil (ANFO) is a low explosive. Each has different applications.

If your other cache of explosives is outside the lethal air blast zone, it is not likely to succumb to secondary (unintentional) ignition... But then again, stuff happens...

jclarkdawe
10-16-2014, 03:00 AM
Thanks, Iron Mike, that's about what I was coming up with. This is definitely an application for high explosives, and the bad guys definitely have access into a lot of explosives. Original application would be high explosives and the bad guys are using somebody else's system that had the explosives stripped out of it.

500 feet seems right. Outside the lethal air blast, and by sheltering from the blast, flying debris risk should be minimized. Keeps my total area within a credible range.

Thanks,

Jim Clark-Dawe

badwolf.usmc
10-16-2014, 04:08 AM
I'll address a couple different things, none of which are classified.

First, I'll talk about Relative Effectiveness Factor (REF). REF is basically the detonating velocity of an explosive as compared to TNT, the baseline for everything. There are other aspects that go into REF but they are not important now. So TNT has an RF of 1.00, with a detonating velocity of 22,600 feet per second (fps), while C-4 has an REF of 1.34, 26,400 fps. Ammonium Nitrate has an REF of .42 at 11,000 fps.

Next we are going to talk about the cratering effect of explosives, or Brisance. Brisance is the shattering effect of explosives, so a higher REF will cut while a lower REF will push. That is where Iron Mike's idea of high & low explosives come and why the military doesn't use C-4 for everything.

The last term is Net Explosive Weight (NEW). The purpose of NEW is to figure out your standoff distances. The formula is this:

Quantity X Weight X REF = NEW

So, So you have one (1) 1lb stick of TNT then here is your NEW:

1 X 1 X 1.00 = 1.00

If you have two (2) 1lb sticks of TNT:

2 X 1 X 1.00 = 2.00

If you have two (2) 1lb sticks of C-4:

2 x 1 X 1.34 = 2.68

Now that you have your NEW, you can figure your standoff. The formula go as such:

K Factor X the cube root of the NEW

Common K Factors:
Blast overpressure without shield: 18
Blast overpressure with shield: 12
Hazardous Fragmentation Range: 300

The cube root of 1lb of TNT is 1.00 so you have the following standoffs:
Blast overpressure without shield: 18 feet
Blast overpressure with shield: 12 feet
Hazardous Fragmentation Range: 300 feet

The cure root of 1,000lb of TNT is 10.00 so:
Blast overpressure without shield: 180 feet
Blast overpressure with shield: 120 feet
Hazardous Fragmentation Range: 3000 feet

badwolf.usmc
10-16-2014, 04:18 AM
http://en.wikipedia.org/wiki/Sympathetic_detonation

This is the term when an explosive detonates another explosive. An explosive charge is nothing more than a series of explosives which are sympathetically detonating each other. I'm not going to give you a formula for this, but as long as your explosives are outside the blast overpressure of each other then they shouldn't detonate.

Also, you don't want to be within the blast overpressure of an explosion. That's bad for your health.

badwolf.usmc
10-16-2014, 04:26 AM
https://www.youtube.com/watch?v=4Wob2ryCfhc

Here is an interesting video of a Mine Clearing Line Charge (MICLIC) in use. Each explosion, which start at 2:50, is 1750 lbs of C-4 going off. Yes, those vehicles are within the blast overpressure range, but they are sealed up so everyone inside is "safe".

jclarkdawe
10-16-2014, 05:10 AM
BadWolf -- Thanks for the help.

I wish I could figure out a way to use that formula. Problem is they think they're calculating missile launch blast not explosions, so the formula is a bit different. But the protagonist needs to have a rough idea of the blast zone when he sets off the explosives.

The sympathetic detonation was a term that's been floating in my head for a few days and I couldn't recall. That's definitely going in the book to explain what's happening. I've got a small shaped blast that's going to trigger the bigger blast, but not all the explosive in the area.

One thing I haven't been able to find is how much space X amount of explosive takes up. Knowing the weight of the explosive that they're using is 1750 pounds, I can calculate the space needed close enough to write it accurately.

Thank you very much,

Jim Clark-Dawe

badwolf.usmc
10-16-2014, 05:32 AM
http://en.wikipedia.org/wiki/C-4_%28explosive%29

I'll post this because it is wikipedia. The specifications they give for C-4 are the following:

1.5" X 2" X 11" at 1.25 per stick.

So 1740 lbs of C-4 is 1400 sticks, and a roughly 1' X 1' X 1' area is 24 sticks. 1400 / 24 = 58.3 and the cube feet is roughly 3.87 feet. So a 4' by 4' by 4' square is what you're looking at. The rough area of the bed for a light pickup truck.

jclarkdawe
10-16-2014, 05:48 AM
This is embarrassing. I looked at that and it never registered.

Argh.

Jim