Scuba scaba, scoobie duba

[Motor62]

Please simplify this for me: I've got a 4500 88 cu tank on back order from pyramid air coming at some point and the only reason I know that will work with my pcp guns is pyramid air told me so. I've tried to read some of the old post about pcp setups, but when I go to eBay or amazon to select a tank, it simply gets confusing. They have scuba tanks, scba tanks, paint ball tanks, 4500, 3400 and 2250 psi. They have different dimensions and then there are the certifications and a lot of other mumbo jumbo.
All I really want is a big tank that. I don't have to have refilled often, the weight doesn't matter, for about $200 used. Can anyo e spell this out for me?

[mobilemail]

Okay, I'm pretty new to this too (so I feel your pain), so I'll try to fill in as much as I've learned.

First, you should make sure you have a place to fill your tank locally before you plunk down the money for one, new or used.  Call and talk to a real person to make sure they can help you.  If you are lucky enough to have a local airgun dealer, ask them for information first because it could save you a lot of time.  Otherwise, you will be looking for dive shops, paintball shops, and possibly fire equipment shops.  You want to ask if they will fill an air tank for you (some dive shops will only do it for certified divers); and if they can fill a 4500psi tank.  Some places can just do 3000psi.  And you probably want to know what they charge.

Now that you know if you can get a tank filled, my suggestion is to make your life easy and buy a new one.  If you make the wrong used purchase, you may get something you can't use or - worse - something you can't sell.

SCUBA - generally 3000psi max.  Old tanks would only go to something like 2200psi, so if you're buying used and it doesn't say, ask.  Most of the aluminum air tanks that you see are 3000psi tanks
SCBA - higher pressure, I think they can go up to 4200psi.  I think most of these are the steel air tanks, and these can provide the most bang for the buck where size and weight are not a concern.  When thinking about weight, remember that you have to heft the thing in and out of the car to get it filled.
Carbon - carbon tanks are lighter and have the highest fill pressure, but they are DOT regulated to a maximum 15 year life.  Watch that date very closely if buying used, I have seen several carbon tanks on eBay that were 14 years old!  That means in another year, you would have a huge water bottle.

Inspections - All air tanks have to have a hydro test every 5 years, and the test date should be on the tank.  If buying used and the last hydro date can't be verified, don't pursue the purchase.  If you buy a tank that fails hydro, you just purchased very expensive scrap.  Tanks also require periodic visual inspections to make sure there are no obvious developing failures. 

Extra costs - make sure the tank comes with a valve, or you will end up buying that too.  And invest in a really good hose that will not rupture after a short lifespan.

Tank failure will be highly damaging to surroundings, and can be lethal.  Again, I would recommend leaving chance to the lottery players and buy new from a dealer familiar with the needs of airguns.  I'm sure any of the "old hands" on this site will fill in any gaps or mistakes I've made.

[starlingassassin]

all valid points.

finding a place for fills is the #1
before even buying a tank make sure somewhere can fill it (scuba shop/paintball shop/fire station)


unless you really know what youre looking at,
buying used tanks can be frustrating at the least,and dangerous/fatal at worst.

if you want lots of fills forget scuba,
you will get the most fills from a 4500psi scba tank.

and as was suggested,
buying new would be the best way for someone new to air tanks to stay safe and be able to enjoy the hobby.

also,
buying from someone that sells the tanks as "airgun" tanks will make sure you have the right connections to fill.

[Oldnoob]

Tom Gaylord has a couple of nice articles on the pyramid air blog. on tanks

[grobe1458]

Please simplify this for me: I've got a 4500 88 cu tank on back order from pyramid air coming at some point and the only reason I know that will work with my pcp guns is pyramid air told me so. I've tried to read some of the old post about pcp setups, but when I go to eBay or amazon to select a tank, it simply gets confusing. They have scuba tanks, scba tanks, paint ball tanks, 4500, 3400 and 2250 psi. They have different dimensions and then there are the certifications and a lot of other mumbo jumbo.
All I really want is a big tank that. I don't have to have refilled often, the weight doesn't matter, for about $200 used. Can anyo e spell this out for me?

you have the right size tank, there are larger 97cf tanks out their, any bigger you're probably looking at nitrogen which some guys here are using.
I prefer to grab used scba 88cf 4500psi tanks as the two I have cost me 200.00 each and have 5 years left on them and were just hydro tested.
buying new is good as you know it's safe. 700.00/15 breaks down to 46.00 per year, used 200.00 /5 breaks down to 40.00 per year.
just buy from reputable places.
if you shoot a lot then you might want to consider a compressor like the freedom series or raptor and be done with lugging tanks around to get filled on top of time and gas.
the cheapest place I have is 8.00 per tank at a dive shop 45 minutes away, the max he can fill is 3500psi, the next shop was 10 minutes away and went from 10.00 to 30.00 per tank (scuba) scba 45.00, my backup paintball shop is 15.00 per fill but 25 minutes away but fills to 4500psi.
so for me it's cheaper to get the raptor compressor especially since the addiction is strong as is the dark side.*L*

[starlingassassin]

dont forget to check out local fire dept's for fills.

they fill my tank for free 

[Motor62]

Thanks all for your replies. I'm. Not sure what I'm going to do, but at least I have a little more information to do it with.

[HYspd]

where are you in SC?

I have an aluminum 80cu ft Scuba tank rated at 3300psi...

it was inspected and certified in 11/2013 and that certification is good until 11/2018

weights about 50 pound when full and I have a fill station that fits the valve on it..

[Motor62]

Hi Hyspd: I live in Greer, (basically the top of the state) . By the way, how many times could I fill my marauder to 3000 psi with your tank?

[Topsportsman916]

I'm new to the PCP world to. I live in a rural area and didn't have fill options. I contacted Joe B. @airtanksforsale.com He suggested using nitrogen,. I contacted my local welding supply and rented a 6000 psi nitrogen bottle. Rent is $105 a year. I then bought a fill set up and a cf bottle from Joe B.

[sr1sws]

I'm new to this too...

I just purchased a used 80cu ft scuba tank (aluminum) rated 3000.  Refills are at the local dive shop.  As I'm not a diver, I had to sign a waiver for filling the tank - basically if I maimed myself, I can't sue them.

I'm filling a Disco, so supposedly it's good for about 70 fills (per Crosman chart).

I'm using a Ninja valve and whip.  Piece of cake to fill, but you have to be careful not to over-pressurize the gun.

One thing no one has mentioned is pre-1989 aluminum tanks - the dive shop tipped me to this.  Somewhere in 1988 they changed the alloy for tanks.  Earlier alloys apparently had a cracking problem and my dive shop would not fill (AL) tanks made before 1990.  Tank I bought was made in 2006 - no issue.

Also valves - there are 'DIN' and non-DIN (K?) valves.  Make sure you know what you get and that it works with your fill station.

My costs:
used tank - $60
hydro - $20 (this was a deal)
visual inspection - $16 (included 1 fill)
12 fill 'air card' - $60 (otherwise $7/fill)
tank boot - $15 (probably not really needed)
Ninja valve - $38
Ninja whip - $30

I also ordered a larger gauge for the valve - just easier to read - I don't have that yet.  $16 with shipping off eBay.

Again, this is for a 2000psi Disco - no good for anything filling at 3000psi or higher.

Hopefully this helps a bit.

Steve

[HYspd]

how many times will a given tank fill your gun....a Fill calculator will help you there....

I like this one from AOA http://www.airgunsofarizona.com/Tanks/FillCalc.html

using my gun as a test case, 80 cuft tank at 3300psi, fill to 3000psi refilling from 2000 psi

a Hatsan air cannon BT65 has a large capacity of 255cc...for 12 fills

to the toon of 25-27 shots per fill, but that's the breaks of shooting an untuned 55fpe .25

a gun with a capacity of 165cc will get 18 fills....

a Discovery filling to 2000 from 1000 will get 61 fills, a Marauder will get 14, BUT dropping 100psi
off the Mrod pressure gets 18 fills....dropping 200 gets out to 23 fills...

dropping 100 psi on the Disco only goes to 67 fills because of the lower pressure to start with...

having a Mrod and a Disco gets interesting because when the tank gets too low to fill the Mrod to
3000psi it will still have enough air to fill the Disco 51 times....one benefit of lower pressure!

[Wheelchair Bob]

Locating an appropriate fill dealer who has a reasonable price is the most difficult part of the equation.  I am working on eliminating my dependence on outside sources and just filling my own as soon as I have enough saved up for a Shoebox Compressor.  The plan is to cascade two 80 CF SCUBA tanks and hard mount everything in an enclosure that I can move easily with a hand truck from Harbor Freight.  All I intend to be visible on the outside is a cascade pressure gauge, a filled tank gauge and an adjustable fill valve so I can add pressure to the onboard tanks slowly to prevent overheating the O-rings in the rifle. All told I anticipate the entire set up to weigh approx. 125 Lbs even with the built in hand truck and spring loaded cord reel to manage the long cord I will use for running the entire system.  I intend for it to have a 50 foot cord length and capable of filling up to 4500 if I run across a HPA SCBA rated for that pressure to carry along as a buddy bottle out in the field.  Wherever I go has to be wheelchair friendly so my deep woods day are over for the time being at least. I will post pics of the build and all of the connections and brackets I make to mount everything securely inside the enclosure,

Wheelchair Bob

[grobe1458]

there is no such thing as a 97 Cube Foot tank they are all the same 550 CI internal volume. 

The 97 CF rating is just a deceptive marketing ploy much like the GAMO ratings with PBA pellets

its technically true but in the real world the tanks are not bigger and the GAMO are not faster

Be careful when reading advertizing there are companies and individuals that want to not so good you in to buying their stuff because it sounds better than everybody else

Please simplify this for me: I've got a 4500 88 cu tank on back order from pyramid air coming at some point and the only reason I know that will work with my pcp guns is pyramid air told me so. I've tried to read some of the old post about pcp setups, but when I go to eBay or amazon to select a tank, it simply gets confusing. They have scuba tanks, scba tanks, paint ball tanks, 4500, 3400 and 2250 psi. They have different dimensions and then there are the certifications and a lot of other mumbo jumbo.
All I really want is a big tank that. I don't have to have refilled often, the weight doesn't matter, for about $200 used. Can anyo e spell this out for me?

you have the right size tank, there are larger 97cf tanks out their, any bigger you're probably looking at nitrogen which some guys here are using.
I prefer to grab used scba 88cf 4500psi tanks as the two I have cost me 200.00 each and have 5 years left on them and were just hydro tested.
buying new is good as you know it's safe. 700.00/15 breaks down to 46.00 per year, used 200.00 /5 breaks down to 40.00 per year.
just buy from reputable places.
if you shoot a lot then you might want to consider a compressor like the freedom series or raptor and be done with lugging tanks around to get filled on top of time and gas.
the cheapest place I have is 8.00 per tank at a dive shop 45 minutes away, the max he can fill is 3500psi, the next shop was 10 minutes away and went from 10.00 to 30.00 per tank (scuba) scba 45.00, my backup paintball shop is 15.00 per fill but 25 minutes away but fills to 4500psi.
so for me it's cheaper to get the raptor compressor especially since the addiction is strong as is the dark side.*L*

so the places advertising them (97cf) tanks aren't being truthful?
if the tanks are 88cf how are they claiming 97cf? even overfilling it the tank would still be 88ft just the psi is higher.

[sr1sws]

so the places advertising them (97cf) tanks aren't being truthful?
if the tanks are 88cf how are they claiming 97cf? even overfilling it the tank would still be 88ft just the psi is higher.

The tanks aren't literally 80 cubic feet or 97 or even 1.  550 cubic inches is about 1/3 cubic foot.  Under pressure, you can put about 80 cubic feet of air in the tank.  I assume the 80 cf is at standard temperature and pressure.

No magic involved and the laws of physics are not violated.

[William]

I have a 100 CF tank rated for 3500 PSI and a 90 CI 4500 Carbon Air Venturi Buddy Bottle From pyramydair... https://www.pyramydair.com/product/air-venturi-carbon-fiber-air-tank-fill-station-4500-psi-88-cu-in?a=4708

I use the 100 CF Scuba tank for my Discovery and the 4500 tank for my Marauder, when the Scuba Tank gets down I just fill my Mrod with it and then top it off with my 4500 tank. I can shoot for a Month or more, mostly my Discovery.

100 CF Scuba tank 3300-3500 PSI tanks-- $278
Fill Valve for scuba tank $45
48" Hose for Scuba tank $40
4500 Carbon Tank 90 CI $299 includes Fill Valve and hose (Fill Station)
Benjamin Hand Pump $179  or 88 CF Scuba Tank Same price, Pump is hiding in the closet collecting Dust lol

Thats a total of $841.00, if you can get the 88 CF 4500 PSI carbon tank ($699 I have seen them a lot cheaper) filled then your better off buying this and saving a few dollars, it will fill a Marauder up 56 times, thats around 1000 shots. It can fill a Discovery up 126 times, thats approx. 2500 Shots at 20 shots per fill.

If i had it to do over again I would have just forgot the pump and would buy the 90 CI 4500 along with the 88 CF 4500 tanks and have the best of both worlds. I do have a couple scuba shops close to me as well as a Paint ball shop to fill my Tanks. I live on the coast. If not I would go for a 6000 PSI NITROGEN Bottle from a welding supply.

Just some thoughts of what you or I would do ( :

William

[HYspd]

an 88 cuft tank is an SCBA tank that is about the same diameter as a 80cuft Scuba but is a solid 6" or more shorter


but yeah it's all about being "rated" which I why I have a tendency to include "rated" when describing a tank..


Motor62...Greer is about 4 hours from where I am...

[Motor62]

There's a lot of information here. Thank you all!