Can one large air tank fill a small air tank

[jgg765]

Hello,
Simple question below can you use one air tank to fill another

Talk to text please excuse any grammar errors
This might sound like a silly question but I'm new to air gunning. I would like to avoid getting a compressor because of the actual maintenance involved and I'm also read about a lot of reliability issues with that being said if I were to get one large air tank and then the second air tank to fill the smaller one could I do that that would give me plenty of shot counts I'm thinking of going and buying one from air tanks for sale the guppy. Can this be done?

 

[EmptyTin_Tim]

Sort of. The thing you got correct is big fills small. However the pressure is also the difference. Pressure will always try to balance between the tanks. So if the bigger tank has more pressure, it will fill the smaller tank. However once the big tank fills the small, the pressure is much less in the big tank and depending on the size difference, may only fill the small one twice or three times.

There's a calculator for you here Tank Calculator

It will also take longer to fill the smaller the pressure difference there is.

You also need to be careful of the max fill pressures because if your 1st tank is a 4500 psi but your 2nd can only go up to 3000 psi, you'd need a regulator otherwise the full 4500 will go to the small tank. Boom.

Also watch your max psi for your gun, too.

 

[Gerry52]

What he said!

 

[rayroz]

it all depends the one with the most pressure wins

 

[beerthief]

I think it might be wiser to get one large and one small , use the large to fill guns and the small one to use while the large is at the fill station . lot of places fill after closing so drop off and pick up .
Depending how much you shoot one of the small compressors might work for you .
I have an Omega trail charger , 3 years old and no problems but i only fill tubes guns i do not have guns with small tanks . although i am sure the compressor would handle gun size tanks .

 

[jgg765]

Sort of. The thing you got correct is big fills small. However the pressure is also the difference. Pressure will always try to balance between the tanks. So if the bigger tank has more pressure, it will fill the smaller tank. However once the big tank fills the small, the pressure is much less in the big tank and depending on the size difference, may only fill the small one twice or three times.

There's a calculator for you here Tank Calculator

It will also take longer to fill the smaller the pressure difference there is.

You also need to be careful of the max fill pressures because if your 1st tank is a 4500 psi but your 2nd can only go up to 3000 psi, you'd need a regulator otherwise the full 4500 will go to the small tank. Boom.

Also watch your max psi for your gun, too.

Thank you!!!

 

[Scouty]

Another option might be a booster for draining the larger tank to a lower pressure. I don't know much about them or if the maintenance and reliability are any better than a compressor. Many people more knowledgeable than me can discuss that.

Altaros makes a bottle to bottle booster as well as a hybrid that also uses a shop compressor. Again, I know very little about them.

 

[LMNOP]

I fill a small tank all the time from a SCBA tank. I am talking a tank so small it could be on a bottle gun. Put the small tank in the freezer first. Boyles and Charles law applies here.

Same principle as filling 1# propane tanks from a 20# tank.