Used scuba dive tanks

[Phoenix02]

Hello all,

I've been reading up on tanks for PCP use and it seems most folks are using the CF wrapped tanks used for FF and emergency air. These I understand have a 15 or 30 year lifespan.

What about dive tanks? They're either much thicker aluminum or steel. I see them cheap, they're heavy, but manufacturing dates all the way back to the 60s, I have seen with current or recently expired hydro and vis certs. 

Does anyone use them? If not, is it just because they're heavy and not range portable friendly? I'm looking at getting a Yong Heng or similar and a tank. I just got a Bulldog and am looking at probably a Xisico Sentry 705 in .25. 

 

[BrickTop]

The biggest issue with dive tanks is most only fill to 3000 psi. Which is no bueno if your gun fills to 3000psi or more. 

 

[biohazardman]

The steel and aluminum dive tanks are lower pressure units usually 3,000psi to 3,500psi. Carbon wrapped are, not only lighter, but most often 4500psi which means several more fills for most guns.

 

[bubblerboy64]

I don’t think they will handle the pressure safely. When PCP’s first came out I think the scuba tanks were the the standard but as the pressure went from 2000 psi to more that twice that it’s pretty much all carbon fiber wrapped stuff. They are expensive but it is what you need and a foolish place to compromise . Talk to Bill Brancato the air tank guy. I think he has the best stuff and can answer your questions.

 

[Phoenix02]

Oh, gotcha. That makes sense. So the aluminum and steel tanks will work with a 3k fill gun or less, but just not hold as much air to refill them.

 

[bubblerboy64]

The issue is both pressure an volume. If you had a 90 CF Tank which could be inflated to let’s say 4200 psi and you had a gun that only used 2500 PSI. You could fill that gun darned near forever off that tank before you would need to refill the tank, if on the other hand the same sized tank which could only be inflated to 3000 PSI would only fill your gun to 2500 way less. WAY LESS AOA has a table you can use to calculate how many fills.
I’d suggest buying a good 74 or 90 cf carbon fiber wrapped tank . Buy once be done with it 

 

[JW652]

Personally, I like large (105 -120 cu/ft) steel tanks that can be pressurized to 3700 psi for home use. Yes you must have an annual vis and a five year hydro. But, a properly maintained steely will last nearly forever. As a DM, I have used steel tanks that were refilled and emptied three times a day - every day for 50 years. Catalina is my favorite brand.

If your rifle has a WP of 3000 -3200 psi, you will get a lot of fills.

 

[Scotchmo]

For a big bore like the Bulldog, I'd personally skip the scuba tank.

An unregulated gun like Xisico Sentry could do OK with the scuba tank. I used a scuba tank for years with my Marauder. It depends on the tune.

Say it's tuned to give a good shot string in the 2500-1500psi range. A 45min (65cuft) 4500psi SCBA tank might give your Sentry 50 fills to 2500psi. If you only fill the gun to 2000psi, you will need to fill it twice as often, but the 80cuft 3000psi scuba tank would give you about 100 fills. So even though you would need to fill your gun twice as often, you'll get the same total number of shots from either the 80cuft scuba tank as you would from the 45min SCBA tank before you need to refill the tank.

If you shoot from a bench, you could tether the scuba tank once it gets below 2500psi, and then you would not need to keep filling the gun.

There are some 3300psi aluminum and HP 3442psi steel dive tanks that you might find. They are a good find if you go the scuba tank route. I mostly use my 45 min SCBA tank these days, but I still have my Catalina 3300psi tank that I use occasionally.

 

[wildcj5]

I have three scuba tanks, two aluminum 3,000 psi and only steel 3,300 psi. I also have one 4,500 psi carbon tank.

If you have the room and are getting the tanks cheap they are great for extending the time between needing air.

Use one or more of the scuba tanks for your start fill and your carbon tank with much higher psi as a top off after the scuba. So you are cascading the air.

Doing this you can end up with that first scuba tank down around 2,200 psi and still be useful. While keeping the higher carbon tank at a higher pressure for longer.

I hope what I am trying to explain makes sense. 

 

[wildcj5]

It’s a little long winded but this guy brakes down what I was saying above and why it’s nice have the extra scuba tanks.



https://youtu.be/1zJfOjqy5tY

 

[JohnnyPDX]

I sometimes use an aluminum scuba tank filled to 3000psi, maybe a bit higher, and tether my Artemis PP700SA to it. LOTS OF SHOOTING!!!

Otherwise get a great compressor. I tried saving money buying a Xisico compressor and it cost me a fortune in money and frustration, not worth it. Bought a HIll EC 3000 and no remorse.

 

[AncientSword]

I used a couple 100cf steel tanks for quite a while. They filled to 3400 and gave me plenty of air for guns that filled to 3k or less. They are fine to start off with if you can find some cheap. I gave mine away to friends once I got setup with scba tanks though. Using one for low pressure and the other to top off works well as suggested earlier.

 

[Phoenix02]

thanks, everyone. I'll keep an eye out for an inexpensive scuba tank, and I'm going to pick up a Yong Heng. I'm in SoCal now, so I'm hoping I can find some dive tanks cheap. We're moving to Kentucky, which I would imagine would have less divers, lol.

-Michael

 

[Humdinger]

The worst mistake I ever made in this hobby was buying a 100CF aluminum scuba tank as my first air source. It's dragging around a bag of cement that gives you 1/3 the fills for 3X the weight and space. Do yourself a big favor. DON'T. Carbon fiber is the only way to go. Buy once, cry once.