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Noah Body
06-02-2010, 09:02 PM
All right smarties, how much C4 would it take to blast a man-sized hole through a cinderblock wall that's about two feet thick?

Mucho Thanko.

Stanmiller
06-02-2010, 09:32 PM
I give up. How much?

Noah Body
06-02-2010, 09:36 PM
:D

Stanmiller
06-02-2010, 09:46 PM
:D

:tongue

I'm wondering something similar myself. I had a guy build thermobarics with a pound of aluminium powder, a dispersal charge and an ignition charge. But I'm wondering if in terms of bang for the buck, a pound of C4 might not have been simpler.

Dario D.
06-03-2010, 10:09 AM
Heh, might need to find a military forum, or something. Few, few people would know the answer to this.

Anaximander
06-03-2010, 12:33 PM
Not a great deal; C4 is seriously powerful stuff. There was an episode of House where a SWAT team use a doorcharge, which is basically a door-shaped plate with a charge on the back that's used to blast a matching hole into a wall to give them an alternate way in. For a wall as thick as the one you're dealing with, you'd need a little more, but at a guess... the charge would be smaller than one of the bricks, if it's applied properly. I have an army friend I'll go ask for you.

Stanmiller
06-03-2010, 04:27 PM
Heh, might need to find a military forum, or something. Few, few people would know the answer to this.

Tried that. Get the 'who are you and why do you want to know' attitude.

jclarkdawe
06-03-2010, 05:02 PM
It depends. Starting point for my knowledge is that I can take out a man-size chunk of cinderblock in about five minutes or less with a sledge. Cinderblock is brittle laterally, while being very strong vertically. Once a small hole is made, the surrounding blocks are not very well supported and destruction can proceed very quickly.

So location of the C4 is going to matter a lot. Placed a foot or so away from the wall, and probably not much effect. Hammer a hole about a foot from the ground and stuff the C4 in, and you're not going to need much. As you play around with location, you can see how differently an explosion would play out. Remember that maximum blast force always proceeds along the line of least resistance, a fact that Hitler could attest too.

Two pounds of C4 will blow up about a foot of frozen ground, providing it is placed in an appropriate drill hole. Ten pounds of C4 creates a nice foxhole, again providing you start with an appropriate drill hole. My guess is a pound, appropriately located, would be enough, while about ten pounds would be more than plenty.

Realize that after the blast, the wall is going to be incredibly unstable. And personally, I'd just take a sledge to it. Beats going to the gym and probably quicker than placing the C4.

Best of luck,

Jim Clark-Dawe

Noah Body
06-03-2010, 05:17 PM
An SF demo bubba got back to me... given the wall texture (brick and wood facade over cinderblock with steel structural supports), the amount of C4 required that would likely do the job is:

Two pounds, seven ounces, if properly shaped.

I'd been waiting for him to answer for a couple of days, which is why I posted it here. He did say I could lose the seven ounces and still come out on the plus side. :D

Thanks, all.

Stanmiller
06-03-2010, 07:02 PM
An SF demo bubba got back to me... given the wall texture (brick and wood facade over cinderblock with steel structural supports), the amount of C4 required that would likely do the job is:

Two pounds, seven ounces, if properly shaped.

I'd been waiting for him to answer for a couple of days, which is why I posted it here. He did say I could lose the seven ounces and still come out on the plus side. :D

Thanks, all.

Thanks for getting the info. In return, want my guy to make a shaped charge for ya? He'll put it in a paint can with an aluminum cone at the bottom to focus the jet and rig the alarm function on a cheap digital watch as a timer.

Dario D.
06-04-2010, 02:58 AM
Tried that. Get the 'who are you and why do you want to know' attitude.
lol, join the club. I'm a video-game designer, so I sometimes think about futuristic military tactics. Once, I sent an email to a US military office about sniper tactics (asking if I could be put in contact with someone that I could pitch some advanced tactics to), and I got a reply suspiciously asking me why exactly I was interested in "sniper tactics" (I thought I had already spelled it out), and never heard from them again. (progress for the win! You'd think they'd be more interested in examining new ideas)

Pretty sure the FBI started a file on me, just in case I get caught using sniper rifles in the future. ;) (they should at least wait till I fling my first rubber-band...)

Noah Body
06-04-2010, 04:44 PM
If you really want good primers on stuff like this, look for the official Army field manuals on the subject. You can find them on eBay. I'd offer to share some with you, but I'm pretty sure manuals on Apache maintenance and assembly area operations wouldn't be of much help.

GeorgeK
06-04-2010, 05:32 PM
If it's actual cinderblock a reasonably healthy person with a 3 pound sledge hammer could go through it in a few hours. Now, reinforced poured concrete would need explosives, but I have no clue how much or what type.

Stanmiller
06-04-2010, 05:57 PM
If you really want good primers on stuff like this, look for the official Army field manuals on the subject. You can find them on eBay. I'd offer to share some with you, but I'm pretty sure manuals on Apache maintenance and assembly area operations wouldn't be of much help.

I have TM-31-210 Improvised Munitions Handbook in hardcopy. It's a valuable thing...