Saturday, September 4, 2010

Airsoft: Survival Skills In Action

By John Durfee

You've been stalking this one for a while. They wandered off from the rest of the group, jumping around, making too much noise. The main group has dismissed this noisy one and decided to stay by the waterside to drink. You're in the spotted shade of a gnarled tree, perfect for hiding your silhouette. You've never been this close to one before. Only 30 yards. Your stalking skills and patience have paid off. There, they've decided to sit for moment, this is your chance. You slowly raise your rifle, and pull the bolt slowly. When you push forward the bolt it clicks, just a bit. Your prey raises their head for a moment, then goes back down to whatever they've been focusing on. You line up the crosshairs, take a deep breath, and smoothly pull on the exhale. CRACK. Direct hit. "OW! Who did that!?!" the teenager looks up from his cell phone, scanning wildly but still unable to spot you. You wave your hand and he quite literally jumps back in surprise. You make your way back into the deeper shade of the woods. The teenager is rubbing a red spot on his forehead. One down, 6 more to go. What I've described is the sport of airsoft, and while fun, can be a great tool for teaching survival skills, hunting tactics, and dynamic firearms training.

Airsoft is different from air rifles and pellet guns in that they use standardized airsoft 6mm plastic bb's that weigh far less than metal pellets or sabots, and are perfectly safe in a controlled play environment.

There are an increasing number of airsoft fields and organizations establishing multiple day events that can be attended for a set fee. They're run on weekends, usually centered around military scenarios, and the core skills practiced are valuable to real world preparedness. You can even learn a few new ones from fellow players. There are varying degrees of immersion, ranging from "play and go back to the car for a snack" to full airsoft milsim, where one acts, functions, and performs like a real military force for the entire duration. These latter are great for putting survival skills to the test. You'll make camp and have to spend one or two nights in the wilderness, so you should pack everything exactly as you'd have your emergency bag. You can practice making your tent or sleeping area using local materials and a tarp. You'll have to bring your own food and water and manage it. If possible, you can research local flora in order to gather and prepare it while immersed in the event as a way to supplement your initial supply. These games are full immersion, so even when you're ready for bed, you have to be alert for surprises coming at a moment's notice. If there's local sources of water, like a stream, water filtration devices can be put to the ultimate test so you know their true reliability. Make sure to ask the event planner if you can practice first aid on "injured" soldiers with faux sprained ankles, cuts, and broken bones using a real First Aid Kit. Also ask if you can bring real equiptment, such as a survival machete or knife, for use in building and cutting down trees. They should be ok with it, but make sure to clear it.

On a recent trip I was tasked to do recon for my group. This was great practice for my hunting and stalking skills, as I followed and marked where the opposing forces were making camp without being detected. Try to get yourself on the "defense" side of an event if they have it, where you have protect and watch a building/compound, that's the more realistic situation you'll most likely be in during an end of society scenario.

Airsoft is also a invaluable way to familiarize yourself with firearms while learning to use them properly for self-defense. Airsoft teaches proper weapon usage, maintenance, and safety precautions. Most airsoft guns in the mid-range price look, feel, and function as close to the real steel guns as possible. Many have the same safety features and levers as their real counterparts. Some gas airsoft pistols even disassemble the same way as the real thing! Real firearms training is great for training how to shoot, reload, and work against recoil, but airsoft simulation events teach valuable self-defense tactics in actual firefights against other people.

Another great side effect of this is physical fitness. Running around all day with limited resources, a full pack, and adrenaline is fantastic exercise. Just make sure to stay hydrated! You'll be sweating a lot more than you think. It also trains your body to react well under stress and flight/fight situations.

These events help train you while reinforcing the survival mindset. You can put all your survival gear through real world paces and determine what works, and lose what doesn't. Working in a team, you're depended upon and also forced to rely upon others. Trust is crucial to any worst-case survival scenario. You have to be constantly aware of your surroundings, because you are a set of eyes and ears for your group. You learn to distinguish between friend and foe. You'll hone your aiming and marksmanship skills on real targets who react and move. All uses of a firearm should be defensive, not predatory, so you'll train yourself how to respond - rather than react - to surprises and potential threats. And if you're "killed" you can learn from your mistakes, so you survive next time!

Try googling the term 'airsoft' and your state, you'll find forums where people get together and arrange outings. Airsplat has a comprehensive listing of US Airsoft Fields. So get out there with your kids and have a safe and fun time!

John Durfee is a Gulf War veteran and the marketing manager for Airsplat, the nation's largest retailer of Airsoft Guns and Airsoft Apparel.

Thursday, September 2, 2010

Detroit Diesel 2-Stroke Series 71, 53, 92 Engines

I put this video on Youtube. It is an Oliver 1950 farm tractor, powered by a 4-53 Detroit Diesel. This is one of the old 2-stroke Detroit Diesels that used to be so prevalent in generators, large boats, garbage trucks, and lots of road tractors. Although the Detroits are very popular, they are unusual in that nearly all competing diesel engines in their size range are 4-stroke designs. Bigger diesel engines, such as those powering ships, are often 2-stroke.

A 4-stroke diesel engine has one or two intake valves and one or two exhaust valves per cylinder, located at the top of the combustion chamber. These valves are actuated by a camshaft, which is geared to turn at half of the crankshaft RPM. It works like this, one stroke at a time:
1. The cam opens the intake valve as the piston moves down, drawing air in through the intake valve.
2. The intake valve closes as the piston moves up, compressing the air. Because of the high compression ratio, the air gets very hot as it is compressed. A few degrees of rotation before the piston reaches top dead center, the injector introduces a shot of fuel to the combustion chamber. The hot air ignites this fuel, which begins expanding.
3. Because the valves are closed, the expanding column of gas has nowhere to go but down, pushing the piston ahead of it. This is the power stroke.
4. When the piston reaches the bottom of its travel,the exhaust valve opens. The piston travels back up, pushing the expended gas out through the exhaust valve. When it reaches the top, the exhaust valve closes, the intake valve opens, and the cycle starts over.

The Detroit Diesel 71/53/92 series 2-stroke engines have a cam too, but it is geared to run at the same RPM as the crankshaft. The cam actuates two or four exhaust valves per cylinder, which are located at the top of the combustion chamber, same as in a 4-stroke engine. But there are no intake valves. Instead, there are intake ports cut into the cylinder wall at the bottom, where they are covered by the piston except when the piston is at the bottom of its travel. Here is a description of operation; in this case we will begin with the power stroke:
1. The exhaust valves are closed and the piston is being driven downward by the expanding gas column. As it nears the bottom the exhaust valves are opened by the cam, and at the same time the intake ports are uncovered by the piston. There is a blower on the side of the engine, driven by a gear from the crankshaft, and this blower blows air into the cylinder via the intake ports. Because the exhaust valves are also open, the incoming air pushes the spent gas out the exhaust valves.
2. The piston starts its upward travel, covering and shutting off the intake ports as the cam allows the exhaust valves to close. Now the combustion chamber is closed, so the piston compresses the air within it, which becomes very hot. A few degrees of rotation before the piston reaches top dead center, the injector introduces a shot of fuel to the combustion chamber. The hot air ignites this fuel which begins expanding, bringing us back to the starting point.

It is worth pointing out that 4-stroke diesels have a high-pressure fuel injection pump which greatly compresses the fuel and distributes it to the cylinder that is ready for it. This pump has precise internal clearances, and is subject to wear if the fuel lacks the necessary lubricity, as in the current ULS, sulphur below 500 parts per million US diesel fuel requirement. It also is subject to damage from water, dirt or any other contaminant. Alternative fuels like waste vegetable or motor oil cause problems too, to varying degrees depending on the design of the pump; but well-processed biodiesel is injection pump friendly; more so in fact than ULS diesel. These pumps are key to the operation of 4-stroke diesel engines, and cost thousands of dollars to repair if worn or damaged.
Current highway diesel engines lack this pump, having instead electrical plunger-operated injectors which are fed fuel from a moderately pressurized, common rail. These injectors are fired by a signal from a computer. If an injector develops a problem, it may be simply replaced.

Detroit Diesel 2-stroke engines also lack the high pressure injection pump. They have a moderately pressurized common fuel rail feeding the injectors, which are fired (and high pressure developed within) by camshaft. These injectors may be simply replaced if they develop a problem, and they are also individually rebuildable. This factor, combined with the very heavy-duty construction of the engine, makes the 2-stroke Detroit Diesel an extremely reliable, long-lived engine.

Wednesday, September 1, 2010

DIY Water Wells

Yesterday I received an email from a reader who has a website about drilling your own water well. I like it. Not only does the site provide in-depth information about how to develop your own water supply; it addresses the possibility that you may not wish to report your new water supply to the county. I like that. Too many information sources go out of their way to withhold information that may empower people to bypass the official control mongers, with the preconceived notion that we are all subservient to, and nothing without, the "authorities".
Anyone who is planning to develop a new water supply on his or her land can benefit from this information.
Check it out, here.