Things That Go Boom In The Night
KA-BOOM: How To Blow Holes Through Obstacles

(by BulletShower, nmatausc@nw80.cip.fak14.uni-muenchen.de)
Hoi all. In Project 3, Carl Rigney has already written something about explosives, and how to calculate the amount needed to blast holes through walls and other obstacles. I looked through my other roleplaying books and found another very good article about explosives, which I find less complicated. It's in the Morrow Project rpg, and I stole it shamelessly :) The following tables assume that you want to blast a man-sized hole (roughly 1.8m) through a wall.

As a rule of thumb, you can say that blowing a man-sized hole into a normal concrete wall requires 3.5 kg of C-4 or C-3. If you want to use another kind of explosive, divide the amount of C-4 by the Relative Effectiveness of this explosive. (C-12, for instance, has a RE of 3, so you need 1.17 kg for the man-sized hole. Using blackpowder (yuk!) requires (3.5 divided by 0.41) 8.54 kg.)


1) FIND THE THICKNESS OF THE OBSTACLE 

Thickness of object     EN - Explosive needed (kg)     
-----------------------------------------
0.5m or less             3.5
0.6m                     4.6
0.8m                     9.2
0.9m                    13.2
1.1m                    21.0
1.2m                    31.5
1.4m                    44.7
1.5m                    48.1
2) FIND THE CORRECT MATERIAL FACTOR 
Material                MF - Material Factor
-----------------------------------------
Reinforced Concrete     1.5
Concrete                1                                        
Rock                    0.5
Masonry                 0.5
Wood                    0.05
3) FIND THE RELATIVE EFFECTIVENESS OF YOUR EXPLOSIVES 
Explosive               RE - Relative Effectiveness
-----------------------------------------------
Amatol                  0.87
Ammonium Nitrate        0.31
Black Powder            0.41
C-12                    3.00
C-4/C-3                 1.00
Dynamite (40%)          0.49  
Dynamite (60%)          0.62
Guncotton               0.69
Nitroglycerine          1.12
Nitrostarch             0.60
PETN (Primercord)       1.24
Picric Acid             0.70
RDX                     0.85
Tetryl                  0.93
TNT                     0.75
4) Multiply the object's thickness by its Material Factor
5) Divide the result from above by the Relative Effectiveness of
the explosive. The result is the required amount of the explosive.
6) Need another size? Multiply the required amount of explosive
by the desired percentage of 1.8m. 


>>>>>[Okay, let's get this straight: I'm a loud bastard and care
drek about noise, so I'm going to enter this corp building via an 
additional entrance. The building is made of concrete, and I know 
that its walls are about 40 cm. So I need 3.5 kilos of explosive to 
blast a man-sized hole through the wall. I use C-4, so I still need 
3.5 kilograms, because the Relative Effectiveness of C-4 is 1, and 
3.5 kilos divided by 1 doesn't change anything. However, I don't 
need a friggin man-sized hole! I'm a troll, and proud of it! I stand 
2.7m tall, so I need (2.7m divided by 1.8m) 1.5 times as much C-4. 
That yields (3.5 x 1.5) 5.25 kilos of C-4. If I had used C-12, I'd
have needed only 1.75 kilos.]<<<<<  --Budget_Waster (no/chance/babe)
     
                              
>>>>>[Hey, Budget, why don't you write:
         
         EN x MF  x  (hole size in m)
         ----------------------------
              RE  x  1.8               ]<<<<<  --Armbruster (not/of/interest)


>>>>>[A drekky little maths drekhead you are, that´s what you are!]<<<<<  
--Budget_Waster (no/chance/babe)


>>>>>[Uh-oh. Never tell a troll she´s wrong, you know!]<<<<<  --Listsurfer (we/all/know) 


>>>>>[What do you mean, 'she'??? I´m a male, you plainbrain, a MALE!]<<<<<  
--Budget_Waster (no/chance/babe)


>>>>>[I know, Budgie, I really know ...]<<<<<  --Listsurfer (we/all/know)






Taken from the pages of Jens-Arthur Leirbakk