Forget Velocity, Think Power!

If I give you a carpenter's hammer, a 2x4 and a sixteen-penny nail, you can drive the nail through the board in three or four hits. If I give you a ten-pound sledgehammer, the same 2x4 and the same nail, and if you hit the nail perfecty, you can drive it through the 2x4 in one hit! The carpenter's hammer is lighter and goes faster, but it does not have the power of the heavier sledgehammer.

I love the claim that a given air gun has a velocity of for example 1400 fps (feet per second). I want to shout out... "WITH WHAT WEIGHT PELLET?" for crying in the moon! I want to know the power factor of this gun- velocity is meaningless and it is only half of the equation without knowing the weight of the pellet!! Faster is not always better in the case of fixed power air guns. Forget velocity, think power!

Power is measured in foot-pounds of energy (fpe) or joules. A .177 caliber BB gun will have enough power to possibly stick a BB into a 2x10 made of Douglas fir at 10 meters. A .50 caliber big bore air rifle will have enough power to put a .50 caliber pellet completely through the same 2x10 like it isn't there and blow out a sizable exit hole on the backside of the 2x10 at 10 meters.

Three Basic Types of Air Guns

So to start you in the right direction, let us take a look at the three basic types of air guns. To keep things simple, we will talk about fixed power air guns as opposed to variable or adjustable power air guns. I will talk about those later.

First, there is the spring-action or break-barrel air gun. To achieve power, a heavy spring is compressed to a locking point and when released by the trigger air is compressed in a chamber directly behind the pellet pushing the pellet forward out of the gun barrel towards the target. In many cases the cocking is done by the barrel itself being the cocking lever, but side levers and under levers are common as well allowing the barrel to stay fixed. As a rule, the harder the cocking effort, the higher the power factor. I would rate the spring-action pellet gun somewhere around 6 to 7 on the power spectrum depending upon the caliber and weight of the pellet.

Next is the Pre-charged Pneumatic or PCP as it is commonly referred to. These air guns receive their power by being filled from a tank like a scuba tank or a high pressure hand pump. An airline is connected to the gun from the tank or pump and the reservoir on the gun is filled to approximately 3,000 psi. When the trigger is pulled, the hammer strikes a valve allowing a burst of compressed air to propel the pellet out of the barrel towards its destination. Again, the rule of thumb being; the higher the pressure, the higher the power. There are 2,000-psi PCP models appearing on the market but again, air pressure equals power. I would rate the PCP at a strong 8 to 10 on the power spectrum depending upon the caliber and weight of the pellet.

Last but not least is the CO2 powered air gun. Similar to a PCP in that pulling the trigger opens a valve allowing a burst of CO2 gas to propel the pellet, the CO2 air gun has about half of the power of a PCP. While the CO2 air gun has a simpler system of introducing power into the gun, the power must be purchased in the form of powerlets as opposed to "free" air. Powerlets come in two flavors: 12 gram and 88 gram and are easily accessible particularly in the 12-gram size. Convenient but less powerful, I would rate the CO2 air gun at 3 to 5 on the power spectrum depending upon the caliber and weight of the pellet.

A Power Spectrum

Most everyone knows how big a common bird is and the size of a typical deer. A BB gun will kill a bird but certainly not take down a deer. Let's think of it as a spectrum of power levels from one to ten. Low power and pellet size being at level one such as a .177 caliber BB gun and a .50 caliber big bore air gun with high power and large pellet size being rated at level ten. An air gun with the power output of 30fpe won't penetrate a 2x10, but one with an output of 60fpe and above will.

CO2 Powered

The CO2 powered air gun has fixed power to the extent that the first few shots are at its maximum power. As the trigger opens a valve allowing a burst of CO2 gas to propel the pellet the power is reduced with each successive shot until there is no power left. The CO2 air gun has a simple system of introducing power into the gun purchased in the form of powerlets. Powerlets come in two flavors: 12 gram and 88 gram and are easily accessible particularly in the 12-gram size.

A CO2 airgun is best suited for target practice, killing tin cans and small game such as common birds. Most are in the .177 caliber range and many have multiple shot capability also known as a repeater. I would rate the CO2 air gun at 2 to 5 on the power spectrum depending upon the caliber and weight of the pellet.

Spring-Action or Break-Barrel

The spring-action comes the closest to repeating the same power over and over. To achieve power, a heavy spring is compressed to a locking point and when released by the trigger air is compressed in a chamber directly behind the pellet pushing the pellet forward out of the gun barrel towards the target. In many cases the cocking is done by the barrel itself being the cocking lever, but side levers and under levers are common as well allowing the barrel to stay fixed. As a rule, the harder the cocking effort, the higher the power.

Spring-action or "springers" as they are commonly called are good for target practice (.177), small to medium game such as rats, squirrels (.22), opossums and raccoons (.25). Not really for coyotes, foxes and animals of that size. Most are single shot and in the .177 to .25 caliber range. I would classify them as medium power or somewhere around 6 to 7 on the power spectrum depending upon the caliber and weight of the pellet.

PCP or Pre-Charged Pneumatic

The PCP air gun has fixed power to the extent that the first few shots are also at its maximum power. When the trigger is pulled, the hammer strikes a valve allowing a burst of compressed air to propel the pellet out of the barrel the power is reduced with each successive shot until there is no power left. These air guns receive their power by being filled from a tank like the AirHog Supreme or a hand pump like the Hill Pump. An airline is connected to the gun from the tank or pump and the reservoir on the gun is filled to approximately 3,000 psi. Again, the rule of thumb being; the higher the pressure, the higher the power. There are 2,000-psi PCP models appearing on the market but again, air pressure equals power.

PCPs in the 3000psi range are considered the "big dogs" of air gunning and have the power and performance to take down medium to large game such as coyotes and deer. I have even heard of a 250lb. boar hog being shot through the head with a .50 caliber air rifle and dropped like a bad habit. From .177 to .25 caliber, many of the PCPs are repeaters that allow you to always have a follow-up shot. 9mm, .45 and .50 caliber are usually single shot, however, some 9mm air guns are repeaters as well. Regardless of what they say, I have found that I like to re-fill a PCP after six to ten shots so that the full potential of power is available at all times. I would rate the PCP at a strong 8 to 10 on the power spectrum depending upon the caliber and weight of the pellet.

A Recent Customer Inquiry

Hello, you have an awesome website and GREAT selection. I was wondering if you could help me out with a product. I live out in the country in Wisconsin and I need a high powered air gun for coyotes and deer possibly. I agree with your statement about the dangers of a real firearm and the loading just to scare away a critter in your yard. So my question is what is high powered enough to kill a deer, coyote and other creatures that come in the yard to terrorize my animals and dig in the trash. Could you possibly email me the options in pistol and rifle if possible.

Here was my response: "Sounds like you would be inside 50 yards to take down your objective... 50 yards is the effective distance for any air rifle and 25 yards for an air pistol.

To do what you need to do will require a pre-charged pneumatic (PCP) which means you will need to fill it with compressed air. Since you live out in the country and AirHog might be impractical, but a hand pump would work just fine for you.

9mm for coyotes and .45 or .50 caliber for deer... You want a humane kill. In 9mm there is the 202S  in .45 caliber, either the 909S or Light Hunter and in .50 caliber the Dragon Slayer and the Dragon Slayer Combo . If you have to settle for one, either the 909s or the Dragon will take care of everything. A 9mm just is not enough for a deer.

As for pistols there is only one- the Evanix AR6... This is a lethal weapon in .22 caliber but you will need to be inside of 10 yards and I wouldn’t use it on a deer unless you can hit it between the eyes. You could use it on a coyote at the same distance but will probably have to give it the coupe de grace with the remaining five shots- it is a repeater and will put a 32 grain EunJin through a Douglas Fir 2x10 at 10 yards. It is also a PCP.

Take a look at my World Famous Suspense Filled Dirt E. Harry Thrillers (LOL) with each gun. Let me know if you have any other questions and when you decide, you will know the magic pellet to get for each gun. These are all purpose built high powered work-horse guns... You will be impressed- Seat belt required."

A General Guide

Here is a general guide that will help you to make an intelligent purchase:

• CO2 .177 and .22 caliber- small birds, target shooting and killing tin cans.
• Spring-Action .177 caliber- small birds, target shooting and killing tin cans.
• Spring-Action .22 caliber- small game (squirrels), medium birds, target shooting.
• Spring-Action .25 caliber- medium game (raccoons), large birds, target shooting.
• PCP .177 caliber- match competition (Olympics), small game (squirrels), medium birds.
• PCP .22 caliber- medium game (raccoons), large birds, target shooting.
• PCP .25 caliber- medium game (wild cats), target shooting.
• PCP 9mm- medium game (coyotes), target shooting.
• PCP .45 caliber- large game (deer), target shooting.
• PCP .50 caliber- large game (deer), target shooting.

The Magic Pellet

Why do I keep referring to the caliber and weight of the pellet? Because it is a very important factor in fixed power air gun performance.

In all of the testing that I have done, I have noticed a reoccurring phenomenon regardless of the caliber: the lighter the pellet, the larger the groups until you get to the magic pellet. Go heavier and the groups become larger again. For example, a .22 caliber AirForce Condor or an Evanix AR6 filled to 3000 psi will put a 32 grain EunJin pellet practically through the same hole over and over with the most penetration at 10 meters. Start the test sequence by using a light weight pellet weighing 11 grains and the groups will be 52mm with little penetration. Progressively move up to a 21 grain pellet and the groups will narrow to 9mm. Move up again to a 28 grain pellet and the groups will drop to 6mm. Go past the magic pellet with a heavier 40 grain pellet (don't do this with the Condor because the pellet will get stuck in the barrel- the AR6 will handle it) and the groups will grow to 6mm again with less penetration. Amazingly, even though the 28 grain pellet has a higher velocity and the 40 grain pellet a lower velocity, the groups are identical and so is the penetration; both being less than the magic 32 grain pellet. So much for the illusive velocity butterfly. To see how this looks, scroll down a ways on my Details page.

Determining Energy or Foot/Pounds- Finding the Magic Pellet

How do you find out how much energy or foot-pounds a pellet has? First of all, it is almost imperative that you have a devise called a shooting Chronograph. Commonly called a "Chrony" it has the ability to measure the velocity of a given projectile. Multiply the weight of the pellet by the velocity of the pellet by the velocity of the pellet again and divide by the constant of 450249 and result is foot-pounds of energy or power. For example, an 8-grain pellet traveling 800 feet per second equals 11.37 foot-pounds of energy. Multiply 8 x 800 x 800 and divide by 450249 gives the result of 11.37fpe.

The easiest way to do this is have a gun vise that is locked down so that it cannot move. Then attach your air gun to the gun vise so that it also cannot move. In the case of a springer, attach it upside down. Set up a target at a distance of ten meters and fire your air gun so that it hits the center of the target. The target can be a simple sheet of 8.5" x 11" copy paper. Move the target, not the gun until you are hitting the center of your copy paper. Lock down what ever it is that is holding your target so that the target cannot move. To see how this is done, please go to my Details page.

Set up your Chrony in front of the barrel according to the instructions, turn it on and begin shooting six to ten of your lightest pellet for your first sequence. Record the weight of the pellet and the chrony readings. Measure the distance between the two farthest holes on your target to determine the size of the group. To see what this looks like, scroll down a ways on my Details page.

Tear off the old target and replace or staple on with a new target, shoot a string of the next heaviest pellet and be sure you put in a new powerlet if your air gun is a CO2 (this may seem wasteful but you have to compare apples with apples) and re-fill if your air gun is a PCP. Repeat this process until you find the magic pellet that is going through the same hole shot after shot. Then repeat the process and use yet a heavier pellet and you should find that the groups are beginning to become larger again.

"Zeroing" Your Scope

Once you find the magic pellet, do not take your air gun out of the gun vise- not yet! This is the time to zero in your sights or your scope. Adjust your open sights so that they line up on the hole that you have just produced by the magic pellet sequence and/or set your scope on your air gun and move the windage and elevation knobs until the scope cross hairs are dead-centered on the magic pellet hole. This way, whenever you take aim in the future, you will know that the magic pellet is going to go where you aim- every time!! You have done due diligence... but stay tuned, there is more!

Adjustable Power- The Magic Air Pressure

The other basic air gun is the adjustable power found mostly in 10 meter PCP .177 caliber pellet guns. Again, it receives its power by being filled from a tank like the AirHog Supreme or a hand pump like the Hill Pump. Because the power needed to propel a lightweight .177 caliber pellet is minimal, all that is needed is consistent air pressure. To provide this constant flow, an internal regulator adjusted by the marksman lets just the right amount of air propel the pellet at the same speed over and over. It does not take a lot of pressure to send a pellet through a paper target; just the magic amount of air pressure usually under 12fpe.

Suppose that you are going to take a one hundred mile trip and your car gets ten miles per gallon of gasoline. Would you rather have a ten, fifteen or twenty-five gallon tank? If you choose a ten-gallon tank and there is a steep uphill grade that was unknown your engine would use more gasoline than estimated and you might have to walk the last few miles to your destination.

If you choose the fifteen gallon tank, you would indeed complete the trip but you would have to fill up before returning; and what if the price of gasoline was higher than at home? If you choose the twenty-five gallon tank, you would be able to go to and from your destination and still have gasoline to spare upon return.

Let's say that the reservoir on a given fixed power air gun is filled to 3000 psi and we want to use a 7.8 grain pellet. After putting the gun into a gun vise we find that at the full power of 3000 psi the pellet travels at 737fps, with 9fpe and produces a 9mm group for six shots at 10 meters. No magic pellet here.

Now lets fill the reservoir on a given adjustable power air gun to 3000 psi and use the same 7.8 grain pellet. We lock the gun into a gun vise and start with the internal regulator all the way open. Same fps, same fpe and same 9mm group. No magic pellet here- yet. Then we turn the internal regulator down and begin shooting again with a new target. At a lower air pressure we see the fps and fpe go down, but we also see the groups begin to get smaller. As the internal regulator is turned down further and to yet a lower pressure, we see the pellet beginning to go through the same hole over and over. Just to be sure, we go a little past and the groups began to become larger again, so we increase the pressure using the internal regulator until we are back to repeating the same hole again. Now we have the magic air pressure which produces the magic pellet.

Hypothetically, lets say that the magic operating pressure is 1500psi and that the reservoir of the gun is now at 2800psi because air has been used to perform this test. This means that we can continue to shoot shot after shot until the gun reservoir drops below 1500psi. then it is time to refill the gun's reservoir because we are now out of useful power.

External Regulators

It is possible to use the same procedure on a fixed power air gun by installing an external regulator such as the Dirt E. Harry Regulator between the AirHog Supreme and the reservoir of the gun. If the AirHog Supreme has 4500psi and we have an air gun with a 3000psi capacity, regardless of the caliber, we can set the output side of the Dirt E. Harry Regulator to whatever air pressure that we need to cause a given pellet to go through the same hole over and over.

For example, if we know that a given .22 caliber air rifle with 3000psi capacity has as its magic pellet one that weighs 32 grains, then we know that a 14 grain pellet will produce a larger group.; the rule being, the lighter the pellet, the larger the groups. However, by feathering down the air pressure to the gun and holding it constant with the external regulator, we can dial in the 14 grain pellet to go through the same hole over and over because we have established the magic air pressure to maintain the magic velocity for a 14 grain pellet. Conversely, if we raise or lower the pressure to the gun, we can increase or decrease the size of the groups for the 14 grain pellet or any other weight of pellet.

Scuba Tanks, the Air-Hog and Hand-Pumps

A little observation about tanks and pumps. Depending upon where you live, consider that when you use a hand pump, you are filling your air gun with ambient air. If you live near the coast and salt air, you are pumping salt air into your PCP. The inner parts of your PCP are made of metal and it is common knowledge what salt air or humid air can do to metal. Take inventory of the air present where you live and consider filling your PCP with clean, pure breathable air provided by a scuba shop. After all, it is the same air that divers breath... something to think about. Out of sight, out of mind will catch up sooner or later.

Most scuba tanks only hold 3000 psi filled. If you have an airgun that can be filled to 3000 psi then the scuba tank will only give you one fill at that air pressure. The next re-fill will be at 2900 psi, the next at 2800 psi and so on.  A 4500 psi tank such as the AirHog Supreme will have "air to spare" so to speak. You will get 35 to 45 re-fills before having to return to your local friendly scuba shop to have your AirHog filled to 4500 psi again.

The Question You Have to Ask Yourself

I hope that I have answered many of your questions. These are questions that I am asked over and over by customers worldwide. You have expressed an interest in the air-gun sport or hobby or you would be at a totally different website. Again, my main goal is to give you what you are looking for- what will best suit your needs. Not just sell you an air gun- any air gun to make a sale.

I know what you are thinking.... do I really offer the best service, cheap prices and the best precision high powered big bore and match grade air pellet guns? The question you have to ask yourself (when dealing with anyone else is...) Do I feel lucky?... well do ya?  Don't be like the message says in the Fortune Cookie. Do yourself a favor... send me an e-mail or give me a call, and Make, My, Day!!... Dirt E. Harry