Safety Warning: Read up on your confined spaces safety prior to trying any of this. https://www.osha.gov/SLTC/confinedspaces/ You can die so easily in confined spaces.
Let me just say first off… I am not an engineer… Civil or Combat. How you go about constructing a DFP (Defensive Fighting Position) is not going to be discussed. Cave ins are a huge risk. Mining is a very risky job. I would not recommend anyone undertake construction unless it is vital to your survival to do so.
Also I am not going to cover the DFP’s that are in the US Army Soldier’s Manual or Common Tasks. A simple Google search will tell you all that you need to know about that.
Now as preppers we have seen a lot of crap be done to build prepper fortresses both above and below ground. I would suggest that instead of looking to make your Bug Out Locations (BOL) look like Helms Deep that you should instead make it look more like the Hobbit Holes of the Shire.
Guess what… You need to consider that you exist on a planet where you don’t have to be the US Government to get Satellite imaging of a particular area… It is called Google Earth. So over head camouflage and deception is important (More info on camouflage can be found at The 15 Commandments of Tactical Camouflage). Not looking like a target is important. Be low key. Having a triple canopy forest will help. It is hard for our thermal and NVG’s to penetrate dense foliage. We are fortunate that all the people who hate America typically don’t have that to aid them. So perhaps we should look back to our last enemy who did…
Defensive Tactics used in Vietnam
The Vietcong had an impressive network of under ground tunnels. Impervious to explosives, chemical, and biological weapons. About the only way to combat these tunnels was to send down “tunnel rats” otherwise known as taking your smallest grunt and giving him hand grenades, a pistol and a flashlight and hope for the best. The tunnels were truly brilliant because it negated a lot of American strengths and played to many of our weaknesses.
If you were to be a tunnel rat I would suggest you get the Taurus Judge and fill it with birdshot. But I would generally advice against this. A lot of the entrances to these tunnels were booby trapped. They also had firing ports fixed on the entrance and firing ports you would have to crawl past.
The Tunnel Systems were extremely complex they had under ground farming, hospitals, ammo dumps, barracks… You name it. I encourage everyone to do the research on the Vietnam Tunnels. They were used to great effect.
Defensive Considerations for Urban Survival
How many times when watching a movie have you seen urban warfare depicted by guns hanging out windows. Yeah that shit rarely happens. Generally you should avoid this. Build up your fighting positions with sand bags. High Caliber rounds… especially a .50 BMG can kill you even if the round doesn’t hit you. Shrapnel from when a high powered rifle round penetrates concrete can kill you. Which is part of the reason why snipers in Iraq were setting all kinds of ridiculous records. They didn’t have to score a direct hit to kill you. Fire from holes in the building or through the roof tiles. Use sniper blinds to conceal your location.
Urban Camouflage and Deception
Graffiti can be your best friend. Spray painting and tagging your own suburban home breaking out the windows and throwing trash out on the lawn. Bio-hazard Bags… Fake Search and Rescue Markings. Bad smelling odors. Anything you can do to make it seem like you really don’t want to enter a place is better than having a fortress… But if you have a fortress just inside from that facade… all the better.
Underground Defensive Considerations
Before using storm drains and other tunnels systems as defensive positions you are going to have monitor the weather constantly. You can easily get flooded in if you are not careful. But this does offer ready made ready engineered bunkers. In WWII subways were Air raid shelters. In South Korea the subway systems are ready to be used to that purpose. You just got to have SCBA with you just in case.
Range Cards… I don’t need to go over this.
You can read how to make a range card here: http://www.globalsecurity.org/military/library/policy/army/fm/3-21-9/apph.htm
But you should fill them out.
If you are going to build a castle or fortress… You might not want to build it based on what looks the most Disney like. At least look at Castle Design when Cannons and Guns were introduced the Star shaped castles really started to take off… When you look at each leg of the star it provides overlapping fields of fire that supports the defense of the others. Over lapping fields of fire is key. Since there was no way to enter the castle but at the center these were highly effective death traps.
Now… Escape Tunnels
Escape Tunnels on the Missile Silos had no entrance. They remained unfinished. The last 5-6 feet of the tunnel you would have to dig yourself. This is ideal. No matter how good of a system you think you have… If someone really wants what ever you are defending they can pour enough ordinance and man power to take it from you. So that Spider Hole guy on Doomsday Preppers… That man is smart. Have an escape plan.
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