Tanks that have 30 minutes 4500 psi

[airborne]

What will these equal to for cu.ft. on air tanks. Lots of air tanks give a psi 4500 but then they have 45 0r 60 minutes. I do not want to buy a tank and not be able to use it to fill my rifle. Yes I am the new guy with all the questions..........Pete

 

[JDShapp]

A 45 minute tank is roughly 65 cu ft. I believe a 60 minute tank is close to 88 cu ft.

 

[BigTinBoat]

"JDShapp"A 45 minute tank is roughly 65 cu ft. I believe a 60 minute tank is close to 88 cu ft.

This is correct, and the 30 min tank hold about 45CUFT breathable air at 4500psi.

Because air is "compressible" the amount of air actually inside of a specific tank will be different as the pressure changes. For instance if you have a 48cuin tank (787cc of liquid volume) if you fill it to 3K psi there will be 5.7cu ft of air in it. If you then fill it to 4500psi (make sure tank is rated for 4500) it will contain 8.6cuft of air.

The biggest SCBA tanks (IIRC) presently made is the 550cu in tank (liquid volume) At 4500psi these tanks are rated at 60 minutes. In CUFT you will see them advertised as 88, 97 and 100 cuft. All of these tanks are the same 550cu in (or 9.0 liter) size. The 88 is "breathable air" and the 97 or 100 are "total air". It's basically an advertising gimmick.

 

[GBGUNNER]

I just measure my tanks in " shots"

 

[lennyk]

45min tanks are the best size to use

you get enough fills and not as bulky as 60min

 

[Humdinger]

"JDShapp"A 45 minute tank is roughly 65 cu ft. I believe a 60 minute tank is close to 88 cu ft.

This is correct, and the 30 min tank hold about 45CUFT breathable air at 4500psi. Because air is "compressible" the amount of air actually inside of a specific tank will be different as the pressure changes. For instance if you have a 48cuin tank (787cc of liquid volume) if you fill it to 3K psi there will be 5.7cu ft of air in it. If you then fill it to 4500psi (make sure tank is rated for 4500) it will contain 8.6cuft of air. The biggest SCBA tanks (IIRC) presently made is the 550cu in tank (liquid volume) At 4500psi these tanks are rated at 60 minutes. In CUFT you will see them advertised as 88, 97 and 100 cuft. All of these tanks are the same 550cu in (or 9.0 liter) size. The 88 is "breathable air" and the 97 or 100 are "total air". It's basically an advertising gimmick.

+1 for you. Years ago Airhog was the pioneer " go to" source for quality carbon fiber air tanks. They correctly and honestly advertised their large carbon fiber 9L tank as an 88cf tank. Then Joe Brancato came along and one upped Airhog by advertising his brand of 9L tanks as 97 capacity as a gimmick to fool the math challenged newbies that would not realize 9L is 9L. Not to be outdone, AofA started advertising their 9L tank as a 100cf tank to fool newbies into thinking theirs was even larger. Let the buyer beware.

My first fill tank was aluminum 100cf scuba tank that only held 3300 psi. My advice is to never buy a scuba tank as your air tank for PCPs. They are a PITA brick to haul around and hold much fewer fills. Don't waste your money. Buy a carbon fiber SCBA 4500 psi tank or save up until you can. After owning and handling 9L, 6.8L, 4.5L, and a 3L carbon fiber tanks, I agree with LennyK in his post above. The best compromise between fill capacity and ease of carry is the 6.8L tank. Smaller ones need refilling more often and the 9L tank is a little too bulky.

 

[Guest]

are these 74-88cf tanks pack able for field when hiking to a location? what kinda weight?

 

[Humdinger]

are these 74-88cf tanks pack able for field when hiking to a location? what kinda weight?

Not really. They are rather bulky and heavy for hiking. My 6.8 liter tank set weighs 16 lbs. with all it's accessories. A 9 liter tank would be over 20 lbs. If you're going on a hike you should get a 3 liter or 1.8 liter sized tank. They are much lighter, smaller, and made for day trips.

 

[sonny]

luxfer has a 106 cu/ft 4350/300bar tank at a reasonable price holds lots of air you wont need to refill as often, comes with 300 din valve (made in usa) 15 year service life.I use one to fill my bottle guns. Says shipping weight 32lbs. Amazon has them but I have seen them elsewhere for around 450.00.

 

[Centercut]

I agree that the 45 minute (66 cu ft.) SCBA tanks are best for most uses. I have three of them (used SCBA but with at least 4 years service life left). I also have one 60 minute (88 cu ft.) tank that I use as a "shop tank" for refilling during testing, builds, repairs, adjustments, tuning, etc... I use that one until it gets down to under 200 bar, but the others I refill when they get under about 230 bar. 

 

[mtnGhost]

I have a 90ci (4.2lb) and a 97cu/ft tank. I keep the larger tank in an old mountaineering pack, and the pack with the tank weighs 28lbs in all when it's full of air.

If I'm hunting for more than a couple of days in the wilderness with a PCP, I will bring my Hill MK4 hand pump with me. It takes a while to fill my Matador with it, but it's about a minute to fill my Leshiy. The extra ~2lbs of weight of the Hill pump over the 90ci tank is worth it to me.