Here at El Rancho Elliott, I probably have at least one example of every single type of airgun powerplant. There are things I like about each type of airgun powerplant, and some things that I’m not so crazy about.
For example, airguns that are powered by 12-gram CO2 cartridges are excellent for family shooting because the cocking effort is usually very low and are convenient because all you need to do is throw a handful of cartridges and a tin of pellets in your pockets, and you’re good to go. The downside of the CO2 powered guns is that their performance can suffer if the temperature drops below 50 degrees or rises well above 90.
Similarly, the good part about spring-piston airguns is that they deliver a fair amount of power for a single cocking stroke. The shortcoming is that you have to deal with the weird recoil of the springer powerplant. And so on.
When it comes to precharged pneumatic airguns, the big why-to-buy is that they are the accuracy champs and generally easy to shoot well. The disadvantage is that they have to be refilled periodically using a high pressure pump or SCUBA tank . . . which brings us to today’s subject.
For almost a decade now, I have had an 80 cubic foot aluminum SCUBA tank that I have used exclusively for filling and refilling precharged pneumatic air rifles and pistols. The guy at the SCUBA shop regards me with deep suspicion (even though I am a certified diver) because this tank has never been in the water and in fact has never been mounted in a dive harness. “It’s just not right,” he says.
I finally bought him around to my way of thinking by bringing in one of the precharged guns to show him. “At 50 yards, this gun will put pellet after pellet in a group you can cover with a nickel,” I said. He reckoned that was pretty neat (he shoots black powder), and I pointed out that, as the owner of a dive shop, he wouldn’t have to worry about a plentiful supply of air.
But I have a love/hate relationship with my insect green aluminum SCUBA tank. It seems like every time I turn around the thing needs to inspected or “hydroed,” which means an extra charge and delay in addition to the normal fill-up. Further, my aluminum tank can be charged only to 3,000 psi. Most precharged airguns take a standard fill of 3,000 psi. So that means as soon as you charge just one air rifle off the 3,000 psi aluminum tank, you will have knocked the pressure in the tank down some. The next gun that you need to fill you will not be able to fill all the way to 3,000 psi, and with each succeeding fill, the pressure will be a little bit less. This will continue until the pressure in the tank will get down to, say, 2,000 psi, at which point it will not be useful for filling precharged pneumatic airguns, unless you have to own a low-pressure gun, even though there is quite a lot of air left in the tank.
In addition, my aluminum tank has a standard SCUBA valve and filling yoke attached to it, which mean you need to have a safecracker’s touch to open the valve just a tiny bit so that you can fill the reservoir on your PCP airgun s-l-o-w-l-y.
Not too long ago, the good folks at www.airgunsofarizona.com sent me an Omega CTF75 carbon fiber tank with a slow safe fill system, and I’ve got to say that it has changed my whole attitude about tanks. The tank is about two feet long and weighs 10 lbs empty. It can be filled to 4500 psi, which means that you can fill a lot of airgun reservoirs to 3,000 psi before you are not getting full-pressure fills. This means far fewer trips to the dive shop.
In addition, the slow safe fill system means that airflow into the airgun reservoir is automatically restricted, so you don’t have to worry about inadvertently opening the valve too far. It’s a lovely system, easy to use, and I am already addicted to it.
So, the bottom line for me is as follows: if you plan to shoot PCP air rifles or pistols and are thinking about getting a SCUBA tank for filling your PCP guns, if you have a shop or firehouse that can fill carbon fiber tanks to 4,500 psi, I would heartily recommend the Omega tank. Sure, it’s more money than an aluminum tank, but it is much more convenient and easier to use.
Til next time, aim true and shoot straight.
– Jock Elliott