Couldn't get the blog to load, either from the link here, or the site itself, Gene. However, it's my experience that using nitrogen, or another high pressure AIR only source, is a safe and widely used practice in the PCP community. I regularly use a 4500# airtank for my own PCP, as it fills to 232 BAR( about 3365 PSI), and when I take it to Airguns of Arizona, I fill it from their 6000# nitrogen bulk tank. The correct filling procedure and precautions MUST be followed as the fill valves are un-regulated. Thus, If one was to open the valve very quickly, or very far, it WOULD be possible to overfill the airchamber beyond it's design limits before you could close the fill valve. Filling must be done SLOWLY, both for safety and to avoid overheating the aircharge, which results in an inaccurate fill.
I get my airtank filled at a local Scuba shop, but for those shooters who live in outlying areas, renting a large nitrogen tank can offer months of fills at a much lower cost than a powered compressor. As with all gunhandling, practicing proper safety rules is above all else.
As an aside, if one doesn't have a scuba shop, check with your local fire department. They use the same type of high pressure airtanks(SCBA) that are commonly sold in the airgun market. Explaining what you are using the tank for, and perhaps showing them your wares, may get you an alternate source to fill your tank. My local department's maintainance shop is just a mile from my home, and I'm call the SCBA tech there today to see if he can hook me up for fills.
Ric G
