The Byrna SD or HD use an 8 gram CO2 cylinder, and the Byrna SD XL uses a 12 gram CO2 cylinder or if the Byrna SD has a Byrna Boost installed it also uses a 12 gram CO2 cylinder.
The installation instructions of the 8g CO2 cylinder and 12g CO2
cylinder are the same.
INSTALLING THE CO2 CYLINDER
Put the launcher in SAFE mode. Remove the magazine and make sure there is not a projectile in the breech.
Point the barrel in a safe direction. Remove the CO2 cap using the cap tool (built into magazine base). If you are replacing a spent CO2 cartridge, there may be a little CO2 left in the cartridge and it might hiss and release a little CO2 and cause the spent cartridge to become cold. This is normal. After you remove the CO2 cartridge from the CO2 chamber and you've confirmed that there is no projectile in the chamber and the safety is on, you can impress others by blowing down the CO2 cylinder like someone from a western movie. After thinking about this, legally, we probably shouldn't tell you to do that, so don't do that.
Insert a new unused CO2 cylinder into the CO2 chamber and use your finger to push the cylinder firmly to the back of the chamber.
Replace the cap using the cap tool. DO NOT OVER TIGHTEN THE CAP. The cap should sit flush with the body of the launcher
When the CO2 pressure falls below a certain pressure the launcher will cease firing. Be cautious, if the launcher is exposed to an increase in temperature, the pressure may increase enough for the launcher to be able to fire again.
Only use Byrna authorized CO2 cylinders in the launcher. Using non-Byrna authorized CO2 cylinders may cause injury or damage to the launcher.
Always remove the CO2 cylinder after use. If the CO2 cylinder is punctured and not removed, premature wear of the CO2 seal may be caused, resulting in CO2 gas leakage.
Do not store the launcher with a punctured CO2 cylinder installed in the launcher, as this may cause premature wear of the CO2 seal resulting in CO2 gas leakage. The launcher may be stored with an unused CO2 cylinder installed.