Are either of these tanks OK?

[Hoosier Daddy]

I have access to two different tanks for free.
Both are out of date on  hydro and will need tested... $40-$45 around here.
First is a welding gas (oxygen) Q size, 83cf bottle. I do NOT see a pressure rating stamp, but the Hydro dates go every 10 years. '86, '96, and '06. I am going to take it to our local welding gas supplier and get details on filling with air.
 The second is a SCBA tank from the local Fire Dept. It's a Steel 30 minute tank that is rated for 2216 psi. They are upgrading to 4500 psi Carbon Fiber tanks and do not want these lower pressure tanks mixed in to prevent accidental over pressuring.
Google says a 2216 / 30 minute tank is 45cf.

I am going to use these to fill my Maximus. It has a 2000 max, It seems to have a sweet spot about 1600 down to 1200 but if I go to another HPA gun it may need 3000.
 Buy the time I buy regulators and hoses, are these tanks even worthwhile to invest the time and money in?

[GLPalinkas]

I think you would be better off buying a used 3000psi aluminum scuba tank (see craigslist) or if you can find one, a 3447psi steel scuba tank. Then you can get a hydro on a tank capable of filling your gun more than just a few times. Most scuba shops will fill your scuba tanks when a hydro and visual check is current. I can't say the same for Fire Dept scba tanks, etc.

A 80cf steel scuba at 3500psi will fill your maximus 167 times from 1000 up to 2000psi. Here is the link for the Crosman calculator. Use a Discovery because they fill the same and use 667(80cf) for water volume under the scuba tank setting.

http://www.crosman.com/discover/airguns/pcp-resources/fill-calculator


Like you, I fill my Discovery 1000-1800 so I get about 160 fills out of my 80cf steel tank when they fill it and it cools to 3400psi.

A steel tank will also give you more fills if you move to a new platform with 3000psi requirements.

[avator]

What he said....

[Hoosier Daddy]

Dag gone it... I had a long post with "twenty seven eight-by-ten color glossy photographs with circles and arrows and a paragraph on the back of each one explaining what each one was..."
But must have not hit "send" before I left work.
In a nut shell, I could get 10 fills from the 2216psi 45CF tank. Another coworker is a volunteer Fireman at another station and fills their same tanks. He would fill the one I get and even mix it in with theirs when it's time to hydro test for FREE!
 I will load up the Q tank (83cf) and take it to the welding gas shop and see what the rate would be.
Then work on regulator and whip.... depending on how I go.

[avator]

Well maybe....
[/you can get anything you want at Alice's welding shopi]

[Hoosier Daddy]

You got it...

[Back_Roads]

Who the heck is Alice... n/m I do know of Arlo Guthre 

[Norm_m]

I would be surprised to see if anyone will fill an oxygen tank with air.

[Hoosier Daddy]

I would be surprised to see if anyone will fill an oxygen tank with air.

That was one of my concerns... Maybe exchange?

Who the heck is Alice... n/m I do know of Arlo Guthre 

Hahahha