Some time ago I was looking at the "Maco2" expellable gas speargun web-site, more out of curiosity than anything else. The "Maco2" guns use either carbon dioxide or compressed air, according to the information on the web-site, which is stored in pre-pressurised cylinders or tanks that attach directly to the gun. The layout of the "Maco2" gun is similar to the fifties "Pelletier" spearguns which actually inspired the creation of this modern version of the guns.
I was surprised to see in the "Maco2" May 2009 catalogue (pdf file from the web-site) the mention of a 250 Bar hand pump, in fact there is even a photo of the pump showing its pressure gauge calibrated to 250 Bar! Does anyone know how this pump works as I cannot believe that a simple hand pump could ever reach that sort pressure, or even half that amount. Plus to compress from ambient and transfer a volume of air at that high pressure to fill a tank theoretically should take an enormous number of pump strokes, it would have to be in the thousands. Adiabatic heating makes compressed gas get very hot, even pumping to 40 Bar with a pneumatic speargun hand pump heats up the lower body of the pump, so you can imagine what over six times that pressure would produce, even if you could push the pump handle down at anything like that sort of pressure. As expellable gas guns consume a lot of gas per shot then hand pumping to pressurise the cylinders or tanks seems to be a crazy idea, but maybe I am missing something.
The 250 Bar hand pump is listed at 285 Euro, maybe it is a bit more than a simple hand pump, it would definitely need to be at that price!
I just revisited the web-site, the pdf catalogue seems to have disappeared, now there is a "shop" menu. You can see the high pressure pump here: http://www.maco2spearguns.com/en/shop.php?cat=Miscellaneous&ref=75
The price of the high pressure pump is now 300 Euro!
I was surprised to see in the "Maco2" May 2009 catalogue (pdf file from the web-site) the mention of a 250 Bar hand pump, in fact there is even a photo of the pump showing its pressure gauge calibrated to 250 Bar! Does anyone know how this pump works as I cannot believe that a simple hand pump could ever reach that sort pressure, or even half that amount. Plus to compress from ambient and transfer a volume of air at that high pressure to fill a tank theoretically should take an enormous number of pump strokes, it would have to be in the thousands. Adiabatic heating makes compressed gas get very hot, even pumping to 40 Bar with a pneumatic speargun hand pump heats up the lower body of the pump, so you can imagine what over six times that pressure would produce, even if you could push the pump handle down at anything like that sort of pressure. As expellable gas guns consume a lot of gas per shot then hand pumping to pressurise the cylinders or tanks seems to be a crazy idea, but maybe I am missing something.
The 250 Bar hand pump is listed at 285 Euro, maybe it is a bit more than a simple hand pump, it would definitely need to be at that price!
I just revisited the web-site, the pdf catalogue seems to have disappeared, now there is a "shop" menu. You can see the high pressure pump here: http://www.maco2spearguns.com/en/shop.php?cat=Miscellaneous&ref=75
The price of the high pressure pump is now 300 Euro!
Last edited: