| By Ben Saltzman
Airguns come in many shapes and forms. You know this to be true
because you just thumbed through this catalog. You think you might want to
own one of these swell airguns but can't understand why Beeman imports so
many when you want just one. I'll give you some basic information so that
you can make a considered choice. Besides the question of caliber, modern
airguns fit into three basic groups defined by their powerplant (means of
pushing a pellet out the barrel).
- Pneumatic Airguns
- Spring-Piston Airguns
- CO2 Airguns
PNEUMATIC AIRGUNS
Pneumatic airguns use compressed air for power. The way you get the air
compressed in the airgun depends on the type of pneumatic it is. The most
common pneumatic airgun is the MULTI-STROKE or sometimes called a
PUMP-UP type pneumatic airgun.
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To get the tiny bit of air compressed in a
Multi-Stroke pneumatic takes, as the name implies, between two and ten
strokes of the forend pump lever to get the internal pressure needed to
power the pellet out the barrel at a decent pace. Most Multi-Stroke
Pneumatic airguns are compact, |
recoilless and light weight. Multi-stroke pneumatics are moderate in
power. The big down side to a Multi-Stroke pneumatic is all the time and
effort needed to get a shot off, and when hunting a second shot is near
impossible before your quarry runs or flies away. As you pump up the
Multi-Stroke airgun each progressive pump takes more effort. Accuracy from a
Multi-Stroke is just O.K. There are too many variables in the pumping
procedure to allow for stellar performance aside from the human error. A
more preferable form of Pneumatic is the Single-Stroke Pneumatic Airgun. As
the name implies, one motion of the cocking lever is all that is needed to
compress the air for propulsion. The SINGLE-STROKE format is used on many
high end 10 Meter Match airguns, such as the Beeman/FWB 603. Consistency,
accuracy and lack of recoil are the reasons top shooters gravitate to this
type of power plant. The downside is lowish power, but with tack driving
accuracy at close range, again the reason 10 meter shooters love them.
| The third type of Pneumatic Airgun is the
Pre-Charged Pneumatic. This is the best of both worlds. You can
get variable power from low to high if you want it. Incredible accuracy,
easy cocking, no recoil and lots of shots from an air charge. The charge
takes little effort on your part because the air is compressed at the
Dive shop |
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into a scuba tank. All you need to do is siphon some of the 3000 psi out
of the scuba tank and into the airgun via a special hose with a pressure
gauge. Pre-charged pneumatics come
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as competition airguns for the field
target set, and lightweight hunters for those so inclined. Some of the
pre-charged airguns are multiple shot repeaters so the airgun hunter
with poor aim can get a second chance with no pumping. |
SPRING-PISTON AIRGUNS
When someone says airgun these days they probably mean a Spring-Piston
airgun thanks to Dr. Robert D. Beeman's relationship with Weihrauch and
Feinwerkbau, two of the best and most prolific makers of high quality Spring
Piston airguns over the years.
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Spring-Piston airguns are the easiest
airguns to shoot, maintain and own. The Spring-Piston gun most shooters
cut their teeth on is the break barrel. The break barrel airgun is
cocked by holding the stock in one hand and breaking the airgun in half
at the breech holding the barrel with the other. This action of breaking
the airgun moves a piston backwards |
within the receiver as well as compressing a stout spring behind it. The
trigger sear clicks into a notch in the piston and holds the whole works in
tension. With a break barrel airgun the pellet is placed directly into the
breech and the barrel is swung back into position and now you are ready to
fire. Take the safety off and put positive pressure on the trigger. When the
sear releases the piston, it moves forward briskly with the power of a big
spring behind it. All this action pushes a column of air forward into the
rear end of the pellet sitting in the breech. The effect of all this causes
the pellet to move briskly out the barrel towards the target of your choice.
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Spring-Piston airguns come in all shapes,
sizes and powers. Spring-Piston airguns are cocked by breaking the
barrel, cocking an underlever, a side lever, or a top lever (overlever). |
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Inside they all are basically the same in principle. Things like spring
rates, diameter of the compression tube (receiver) and swept area can be
different depending on the gun designers ideas. Spring-Piston airguns are
very reliable and long-lived. The worst thing you could do to any
Spring-Piston airgun is to "dry fire" it; that is, fire it without a pellet
in the breech. What happens when this error occurs? The piston head is
smashed into the front of the receiver (compression tube) because the
missing pellet cannot offer the needed resistance to the air column. This
resistance cushions the piston from the tremendous energy the ompressed
spring releases to move the air column. Spring-Piston airguns last a long
time, but the springs do wear out after awhile. Do not worry. A spring
piston replacement and piston seal change are relatively cheap and very easy
for an airgunsmith to ccomplish, but again we are talking years of use and
thousands of pellets. Most firearms shooters like the recoil sensation felt
when shooting a spring airgun. This is a smooth steady push to the shoulder
as the spring inside the airgun does its work pushing the pellet out the
barrel.
CO2 AIRGUNS
As their name implies, these airguns are powered by CO2, either in the 12
gram cartridge form or decanted from a bulk CO2 tank into the airgun
reservoir.
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This all depends on the airgun. CO2 as a
power plant for an airgun is kind of funny because it is used in some of
the mass-produced non-precision airguns along with the highest of the
high-tech 10 meter match airguns. Kept at room temperature, CO2 is
approximately 900-1000 psi and very |
consistent, but raise or lower the temperature and the point of impact of
a CO2 airgun can change. You wonder with this point of impact change
situation why would these serious match shooters choose the CO2 propulsion
system to break records. Well, these people are smart. They bring their CO2
airguns to the range, let the airgun stabilize to the ambient temperature in
the range and sight in. Right-left (windage) point of impact will be
constant, your up-down (elevation) zero will vary slightly until you sight
in. The real issue with CO2 as a powerplant is for the airgun hunter or
plinker. The airgun hunter who sights in on a warm day and goes out to hunt
on a cool one or visa-versa will not know where the airgun will hit. A
temperature change during the day will also be a problem. CO2 airguns are
generally easy to cock and recoilless to shoot. The match CO2 airguns are
very consistent and incredibly accurate at 10 meters.
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