Importance of Good Quality CO2
 Many of the air pistols and Real Action Markers serviced at our gun
benches involve inoperable and clogged valves or deteriorated o-rings
and seals. More times than not, its evident that a lesser quality CO2
cylinder was regularly used in these airguns and markers. The
performance life of your CO2 gun’s valve and seals depends heavily
on the cleanliness of the CO2 you’re using as well as the type
of seal the cylinder creates against your airgun’s o-ring. Dirty
CO2 can also cause diminished velocities and equate to fewer shots per
cylinder.
 There are several brands of CO2 cylinders to choose from and without
being able to see inside of each cylinder, it is impossible to know which
brand or brands offer the cleanest CO2 and are of the best quality. CO2
cartridges also come from various manufacturers and countries, all of
which have differing standards of quality control. Each cylinder has
to conform to size, weight and temperature threshold specifications,
but there are no regulations governing the cleanliness of the CO2 or
the cylinder, so it is hard to know which is the best without testing
each and every one—you could go through several o-rings and destroy
a valve or two before figuring out which is best.
Because
of the number of “bad” seals and valves we were seeing,
we cut open some Walther/Umarex
CO2 cylinders and some leading branded
CO2 cylinders. We were amazed at the difference.  The leading brand
had extraordinary amounts of oil and grit lining the walls of the cylinder.
The Walther CO2 cylinder was clean. The color, texture, and smell of
the grime in the leading brand cylinder was consistent with what we
were seeing on our gunsmith bench and is what we determined to be the
main cause of most of the “bad” o-rings and valves we were
seeing in the airguns coming in for service.
Another issue we often have calls about is CO2 leaks. The most common
leak is caused by a CO2 cylinder’s tip making a bad seal against
an o-ring. CO2 cartridges are filled with liquid CO2 and then capped.
There are at least three different styles of caps and one may work better
than another in your CO2 gun. Take a close look at the valve where your
CO2 cartridge fits into the airgun. If the cartridge simply presses against
a seal, most of the time any of the three will work. If your cartridge
slides through an O-ring, you could experience leaks if you use the wrong
kind of cylinder. Take a look at the three CO2 cylinders in the picture.
The cylinder on the left is totally crimped on. The one in the middle
has a pressed on top that leaves a groove
around the neck and the one on the right has a smooth neck. If your airgun
has a slide-through o-ring, the style on the right is the only style
of these three you should use. Walther
CO2 cylinders are produced in
this fashion and the only kind we use in our airgun testing facility.
 You will also notice in the picture that the dimensions of the neck
and shoulder of the cylinders vary. We see many instances where leading
brand cylinders (the first and second cylinders from left) will not fit
properly into an air pistol and then will not pierce correctly due to
incorrect dimensions. Do not apply excessive force or use pliers to get
these ill-shaped cylinders in your airgun. Doing so could damage the
gun’s frame and/or puncture assembly.
One final tip to consider, and the easiest to do, always put a drop
of RWS Chamber Lube on the tip of each CO2 cylinder before installing
it. Doing this will extend the life of your valves and o-rings and can
prevent leaks. This one simple tip alone could save you a service call. |