While at my local propane supplier recently I noticed that they had 50cf and 100cftanks of compressed (1800psi) 'Balloon grade' for sale or rent. Back in the 1980s, I tested the increase in shot power for different airguns when run on Helium compared to air for posting on the old Yellow Forum. The relatively recent development of high-power PCPs with adjustable regulators and variable power bypasses most of the motivation for increasing airgun shot power by using Helium. But I was still curious to see if using Helium in a friend's regulated .22 Notos carbine would significantly increase the shot power compared to using air.
Here are some test results for the velocity and FPE for 12 kinds of pellets, tested with air and then with Helium. The actual % power increase resulting from using Helium depends on the specific brand of pellet. On average the power gains were roughly in the 40% range (from ~20fpe on air up to~27fpe on Helium). That's a modestly substantial power increase for are relatively low power carbine like the Notos which has limited options for power adjustment.
The topic of Helium has come up many times on different airgun forums over the years. I've rarely seen any actual power curve tables posted with test results for different pellets in different airguns though and wanted to post the results as a reference for anyone searching the forum for Helium. Even though commercial cylinders of Helium were only available in 1800psi (50cf) and 2200psi (100cf) cylinders, it was simple enough to feed low-pressure Helium directly into the intake port on a compressor for 300+ BAR.
It would probably be more interesting to see some air vs Helium power comparisons in the unregulated Huben GK1 pistols at different settings on the power adjustment control. Especially for the Shortened version of the .25 GK1 pistol, which is easier to carry and holster than the standard full-length GK1, but also has a somewhat reduced power output on air compared to the full-sized GK1. It would involve considerably more power tests than on a Notos due to the lack of a regulator and very high gas flow through the GK1 at higher power settings. However, it would also be very interesting to know if a shortened GK1 run on Helium would produce a significantly higher maximum shot power than a standard GK1 run on air. At least for the first few highest-power shots after recharging which people always seem to focus on when posting their 'maximum power produced' results.
JP
Here are some test results for the velocity and FPE for 12 kinds of pellets, tested with air and then with Helium. The actual % power increase resulting from using Helium depends on the specific brand of pellet. On average the power gains were roughly in the 40% range (from ~20fpe on air up to~27fpe on Helium). That's a modestly substantial power increase for are relatively low power carbine like the Notos which has limited options for power adjustment.
The topic of Helium has come up many times on different airgun forums over the years. I've rarely seen any actual power curve tables posted with test results for different pellets in different airguns though and wanted to post the results as a reference for anyone searching the forum for Helium. Even though commercial cylinders of Helium were only available in 1800psi (50cf) and 2200psi (100cf) cylinders, it was simple enough to feed low-pressure Helium directly into the intake port on a compressor for 300+ BAR.
It would probably be more interesting to see some air vs Helium power comparisons in the unregulated Huben GK1 pistols at different settings on the power adjustment control. Especially for the Shortened version of the .25 GK1 pistol, which is easier to carry and holster than the standard full-length GK1, but also has a somewhat reduced power output on air compared to the full-sized GK1. It would involve considerably more power tests than on a Notos due to the lack of a regulator and very high gas flow through the GK1 at higher power settings. However, it would also be very interesting to know if a shortened GK1 run on Helium would produce a significantly higher maximum shot power than a standard GK1 run on air. At least for the first few highest-power shots after recharging which people always seem to focus on when posting their 'maximum power produced' results.
JP
Last edited: