doubleh
Member
Yes, but there is a tremendous difference in the amount of pressure and the higher the pressure becomes the harder that handle is to push down. The volume is tied to the pressure level, more pressure, more air in the same space.
I want a PCP, but I am cheap
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Mauser lover
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Well... Sort of. Volume is always volume. The higher pressure will influence the effort of using any given pump. However, a different pump may have a different ratio of volume to surface area, which will influence the effort of using it.
My post was merely to point out that it isn’t all that big of a job on most guns. I do concede that it requires less energy to pump up a 500 cc (17ish fl oz, if you want to match units) pressure vessel to 100 than to 1000 psi.
Mauser lover
Member
The volume of the container is different than the volume of the low-pressure air that will go into the container. It’s a gas, so it will always fill the container it’s given. Once it’s in, it’s the same volume.
So, if you have a tank that's rated to say, 3000 psi, and at that pressure it's holding 80 CF, is the tank the same volume of gas when it's at zero psi?
Mauser lover
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It depends how you read your question. The tank is always going to hold 80 CF of gas, whether that gas is at 3000 psi or 0.
If we take the 80 CF of 3000 psi gas out of the tank, the gas’s volume will increase until its pressure matches its environment. The gas is going to be a greater volume at 0 psi than at 3000 psi.
I think welding tanks are sized to be a specific volume at a specific pressure above standard atmosphere. So when you buy argon or co2 you are actually buying a specific mass, not purely cubic feet. It may actually be easier to think about this in terms of mass than volume. In that case, the mass of a given gas in your 80 cf tank is going to be greater at 3000 psi than 0 psi. There are more molecules stuffed in there.
MedWheeler
Member
HJ857 writes:
Unless it's at total vacuum (in which case, the gas would be absent), yes. The gas just won't have the same density and, therefore, it won't have the same mass. The gas will still fill the tank to volume, though.
That's why your cereal boxes are "sold by weight, not by volume", because "volume" is not as consistent as mass (weight.) If your Frosted Flakes expanded like a gas does, it wouldn't settle before reaching the top of the box, and you'd end up with less product (which would fly out once the package was opened!)
Unless it's at total vacuum (in which case, the gas would be absent), yes. The gas just won't have the same density and, therefore, it won't have the same mass. The gas will still fill the tank to volume, though.
That's why your cereal boxes are "sold by weight, not by volume", because "volume" is not as consistent as mass (weight.) If your Frosted Flakes expanded like a gas does, it wouldn't settle before reaching the top of the box, and you'd end up with less product (which would fly out once the package was opened!)
Mauser lover
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Mauser lover
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I'd say! That's quite impressive at 100!
jmohme
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surprised me too!
the replacement is pretty good to, but not nearly as consistent as the first one.
KevininPa
Member
I'm startong to consider one of these. How do you like yours? I want something to reach out further than my Talon Ss(12 inch barrel). Also like the idea of the lighter weight it has.
Mauser lover
Member
Well... It was cheap enough for me to bite. I haven't shot it at 100 yards yet. I get plenty of shots per fill, but keep it pumped up pretty close to full all the time (I don't shoot more than about ten shots at a time, then I'll just top it off). It stays loaded next to my bed for midnight excursions against marauding raccoons, and does pretty well at that task. Unfortunately, this was not the use I had in mind for it when I purchased it! I haven't even mounted the scope I intended to use on it, due to using it more at night than I thought I would. Just irons and a handheld flashlight at the moment.
It works well enough to convince me that at this point I would be wasting money (for my uses) on any more spring guns.
KevininPa
Member
I like that. How heavy is it?
KevininPa
Member
I have the Talon SS for pest control. There's a red varmint light mounted on it and it's sighted in for 25-35 yards It will reach out to 50 but I'm pushing the limits of the 12 inch barrel then.
I like the Stormrider option for its weight. The wood stock is only a little over 6 pounds. The synthetic, a little over 5, I believe. Even scoped, either can be easily carried in the field. And the longer barrel will give me some more range.
Mauser lover
Member
I've got the wood stock, and it isn't heavy at all. Add a sling and you'd have a nice, handy rifle for hauling around.
What velocities and groups are you seeing from your little Talon?
KevininPa
Member
I set it up for 775 max a long time ago witha chrony. After about 40 -50 shots, will work its way down to about 725. It's an older one, unregulated. I can keep it in a dime at about 25-30 yards. Perfect for squirrels heads! Also do all my shooting freehand. Practice that way because pests don't want to walk where you want them too!
I went from no PCPs to three in the last couple of months augmenting my break barrels and pumpers. I got a Gamo Urban .22, a Umarex Gauntlet II .25 and the Benjamin Marauder .25. Of the three, the Urban may be the most accurate and it is light and handy but it leaks from the air tube main seals despite my replacing them now twice. It also leaked from the fill port which I was able to fix. The Gauntlet is huge and ugly and accurate and powerful and can shoot and shoot with that huge scuba tank on the end. And the built in USA Benjamin Marauder (with a Turkish walnut stock) is a cut or two above either and feels like a real rifle and shoots wonderfully. I did refinish the stock to give it a little better color, sorry for the poor picture, it was too cold out to pose it better:
I will eventually get that Urban fixed, I just ordered some silicone O-rings and have a plan of action, but it is irritating. I think there are some scour marks inside the tube that I will need to polish out, here I installed the GRT-4 trigger, upper photo, it is aluminum and has a crisp pull:
3C
I will eventually get that Urban fixed, I just ordered some silicone O-rings and have a plan of action, but it is irritating. I think there are some scour marks inside the tube that I will need to polish out, here I installed the GRT-4 trigger, upper photo, it is aluminum and has a crisp pull:
3C
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