It is heavy, but thats not why I tried helium. I've seen some use of helium and have access to it, so I thought I'd try it. I expected a little boost, but WOW. My back yard friendly gun turned into a scream from my wife and the neighbor dogs to start barking. 1199 FPS with a 20 gr. .25! Supersonic out of an airgun is a cool sound. Don't know if I'll try it again.
Hatsan is too heavy, so filled it with helium
- Thread starter Polardoo
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Yikes! Reminds me of 1976. My dad had been in the navy and had a real m-80. It was 15 years old and he lit it figuring it was so old it would probanly just fuzzle. Well as you can imagine the neighborhood all came outside to see who blew up a car. The sound actually rattled windows and caused every every dog to start barking. It didnt take long for the police to take a drive down the street. We hid in the house for several hours. Dad wasnt allowed to play with fireworks after that lol.
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LOL.. My very favorite childhood toy! We could get them for 10 cents from a guy in the neighborhood. I would take my wagon and go around collecting soda bottles, which were deposit back in those days. I'd get a dollar and go buy 10. Then start looking for stuff to blow up.
My mother's mop bucket didn't survive a tragic drive by explosion. LOL.. She was really mad. How was I supposed to know that if you fill it with water and drop in an M80 with a stone tied to it with a rubberband, that the bucket would self destruct? I was only 10 ya know.
Crusher
ps. sorry, didn't mean to hi-jack. He mentioned the M80 and the memories just came flooding in.
My mother's mop bucket didn't survive a tragic drive by explosion. LOL.. She was really mad. How was I supposed to know that if you fill it with water and drop in an M80 with a stone tied to it with a rubberband, that the bucket would self destruct? I was only 10 ya know.
Crusher
ps. sorry, didn't mean to hi-jack. He mentioned the M80 and the memories just came flooding in.
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Cool stuff, I would be interested in how long your tank holds a charge as helium atoms are small enough to permeate rubber seals. The same reason that helium balloons deflate or some dive watches have a helium release valve.
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interesting. is helium under that high of pressure in tanks that you can fill a pcp with it or are there more steps to the process? also how long does it hold a charge with helium as asked above. didn't know that about dive watches. I would love to get my hands on some real m80s good times.
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I have a .457 Extreme Big Bore that holds 4,500 PSI of helium. It doesn't leak, I filled it at the end of one deer season and when I went to top it off several months later it didn't need any. First shot sends a 250 grain hp @ 1,300 fps. Second shot is much less but still enough to hit something at 100 yards for a kill shot. My Impact has a leak between the bottle and the regulated chamber, very slow, takes a few weeks to drop noticeably. But if I remove the tank the chamber holds a charge so I just unscrew the bottle when not using it. Basically if your o-rings are good it holds just as good as air. And only the latex balloons leak helium because they are more permeable. That is why the helium balloons they sell in the stores use Mylar balloons instead, they last for weeks. Some things can't hold it because they are semi permeable, o-rings have no problem holding it.
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Hi is great for power if you can afford it. It will find a leak on a rifle that doesnt but it holds well in any well sealed rifle.
I dont want to quote number off the top of my aged brain but the power increase in a Career 707II .25 using 39.9g solids was remarkable. Even if you get the fps down under sonic it still has a loud high crack you'll never get rid of. Never had the chance to try it in a big-bore but it seems the ticket for hunting and I wouldnt worry about it leaking out in less than couple of weeks. Nevr seen the 6,000psi tanks outside a shop, low psi and you'll need a booster. For kicks a person could get a party tank ( often not as pure ) at wallymart hook a hose up to a hand pump , might be about 12lb of boost there?
Might need some 40g if you keep using it.
John
I dont want to quote number off the top of my aged brain but the power increase in a Career 707II .25 using 39.9g solids was remarkable. Even if you get the fps down under sonic it still has a loud high crack you'll never get rid of. Never had the chance to try it in a big-bore but it seems the ticket for hunting and I wouldnt worry about it leaking out in less than couple of weeks. Nevr seen the 6,000psi tanks outside a shop, low psi and you'll need a booster. For kicks a person could get a party tank ( often not as pure ) at wallymart hook a hose up to a hand pump , might be about 12lb of boost there?
Might need some 40g if you keep using it.
John
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You can get a 6K Helium tank from a welding supplier. The tank is rented and you pay to fill and re-fill.
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The tank I filled off was at about 1800 psi, I topped off with my compressor to 2800, so it would be interesting to crono 100%. Its just something I can't use though, too loud for backyard and after the first shot, prairie dogs all disappeared.
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The guy explains near the end how he boosts helium pressure from a low pressure bottle.
https://youtu.be/dAjZ8GYdqx8
https://youtu.be/dAjZ8GYdqx8
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You can also supply your booster pump with helium to get 100% up to your fill pressure. I attach a helium hose to my shoebox to fill my carbon fiber tank to 4500 psi of helium when my 6k tank falls below 4500.
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