Bulk Filling CO2
If you are new to airguns, you probably have noticed that the majority of airguns available today that shoot pellets and BB's (not paintball guns) and are CO2-powered seem to run on the 12 gram CO2 cartridge. They are convenient to use, readily available at many locations, and provide ease of carry if you are in the field and need a refill of CO2 to power your gun.
There is a term thrown about called "bulk filling". If you haven't heard of this before, it simply means that rather than the 12 gram cartridge, you have elected to use a much larger reservoir of CO2. To do this, you need to get liquid CO2 into your gun's reservoir so that as you shoot, the gun can replenish quickly its store of gas.
Years ago, right after WWII, Crosman used bulk-filled CO2 guns almost exclusively, and even sold the guns with an accompanying tank that you could get refilled for pennies. Even today, a 20-lb. tank of CO2 is not all that expensive, and the popularity of paintball was built on CO2, so it is easy to find and use.
Airgun manufacturers still make CO2 bulk-filled guns, but there is quite a bit of profit potential in supplying CO2.....and they have capitalized on the consumer's need of CO2, which is why they sell the cartridges by the millions each year. The airgunner without gas for his gun is a sorry sight indeed, and in this disposable age we live in, buying the cartridges is our answer to our shooting needs.
However, there are still ways to take advantage of the bulk-fill process. Two easily converted guns that come to mind immediately are the Crosman 2240 pistol and the QB-78 rifle. In the case of the Crosman 2240 pistol, a "fake" CO2 cartridge can be inserted into the gun, and a hose connected to the "fake" cartridge feeds a constant supply of CO2 to the valve. This gives great shot consistency, and allows 100's of shots per fill rather than 30 or 40. The methods of bulking a 2240 include suspending a bottle below the gun after drilling and tapping the reservoir, or using a new endcap that has been replaced with an adapter allowing for a constant gas supply. The bottle can also be placed inside the plastic shoulder stock that Crosman sells, with a gas supply line running to the reservoir and "fake" CO2 cartridge. Here is a link to some photos of what I'm talking about:
In the case of the QB-78, a different approach can be used. One can simply replace the endcap with a factory-made bulk-fill cap that allows you to fill the rifle's reservoir with liquid CO2. In addition, a model of QB-78 called the QB-78T now comes with a truncated reservoir fitted with an adapter which allows you to screw in a 9 oz. bottle for literally hundreds of shots.The following link will take you to a hobby site that an individual put up concerning his QB-78's and what he has been able to accomplish with them:
You will find several informative posts at the above site that will guide you in moving to a bulk-fill existence should you choose to do so.
Bulk-filling also allows you to stretch your dollar quite a bit further. I don't shoot near as much CO2 as I used to since I have PCP setups now, but I do know that I'm still working on the same tank of CO2 I acquired 3 years ago. Whenever my small tanks for my LD Pistol or QB-78 run out, I just refill them in the garage, and so far I still haven't had to buy anymore CO2!
Gas guns like the CO2 guns mentioned above are fun, very accurate, and easy to use. New shooters can use them with a minimum of instruction, and accomplished shooters get quite a kick out of modifying and stretching the abilities of these guns through bulk-filling and tuning. Enhance your shooting fun by exploring the world of bulk-filled CO2 guns, and be sure to search through Airgun Depot's website for the items you'll need!
