Scuba tank

[crankythunder]

I just purchased a Steyr LP50.

Took my old scuba tanks to get air and the salesman said that my tanks are old steel with max rating of 2,400psi. Recommended that i get either a 3,000psi aluminum tank or a 4,500psi carbon fiber tank.

When i was diving regularly i remember the scuba stores being hard salesmen. Only the best and brightest will do.


Do I need to get a new $300.00 aluminum tank or will my old steel tanks suffice? Carbon fiber tanks?

Thank you.

Cranky

[Rover]

I was diver and am now an AP shooter. I NEVER heard of anything like that, and am now shooting a recently inspected steel tank.

[PeeWeeDaddy]

Depends.
I do not know how much air your pistol holds.
But, you should be able to get a few fills out of the small tank.
A 4500psi Carbon Fiber SCBA tank should provide you with one 100+ fills, however.
Note: Unlike your steel tank Carbon Fiber tanks only live for 15 years and must be re-certified every five years.

[m1963]

Dive tanks are marked for pressure rating. Here is a link as to deciphering the markings...

https://greatdivers.com/scuba-gear/tank-markings/

[Gwhite]

This can be an issue. The school where I coach pistol has a scuba class that uses old "low pressure" (2400 psi) steel tanks. They work fine for a 1 hour class in a swimming pool. The school's compressor is set to a lower maximum pressure to safely work with those tanks, so it's not very useful for our PCP pistols. We haul them off to the local dive shop to get them filled. There should be a marking on the steel tanks so you can check if the dive shop is on the level, although reading all the stampings can be a challenge.

If your tank is that old, it would need hydro testing anyway. I'd pick up a used aluminum tank and get it tested. They are often available cheap on Craig's List. Just to be safe, I wouldn't get a tank that is rated for more pressure than your pistol cylinders, which is typically 3000 psi. An 80 Cubic foot tank will last a LONG time unless you shoot a lot.

[marky-d]

I'd reiterate pretty much what everyone else said. In your position, I'd use your steel cylinder unless (1)you want to get some extra shots out of each fill, (2)it has the wrong fittings to adapt to your LP50, and/or (3)you feel like spending more money for new stuff.

I believe your LP50 has a 200bar (2900psi) rating, so a readily-available aluminum cylinder from Craigslist will allow you a complete fill, rather than the <2400psi of your steel cylinder. If you can find one that's full, and with the right valve, you're good to go; otherwise you'll need to spend the money to have it filled (and likely hydro tested). Most aluminum cylinders I come across have K-valves, so you might need to buy and install a new DIN valve too (or an adapter). A lot of new valves convert, but that may not be what you find on Craigslist.

In my opinion, a 4500psi carbon cylinder is overkill, and technically dangerous, as you would have the ability to over-pressurize your LP50. Or you can just have it filled to 3000psi to be safe, but then you're wasting most of the reason to have a carbon cylinder (more capacity).

When it comes down to it, pressure is pressure, and it doesn't matter what container it's in as long as you can connect it to your gun and you can get it filled. Personally, I fill my guns from old carbon cylinders because I used to work in the industry and I have them (and adapters to convert from SCBA to DIN valves) available. However, I'll never be able to get them refilled legally because, as PeeWeeDaddy noted, they are past their 15yr "lifespan". When I finally use enough air from them to make them less useful, I'll probably start using my 3000psi aluminum cylinders because my pistol is rated to 250bar (3600psi) and I don't know if I'd get enough shots from my 2400psi steel cylinders.

But in a pinch, I'd use my REALLY OLD steel cylinder that is only rated to 2250psi -- it was made some time around the middle of the last century, but passed it's last inspection and hydro test (in 2010) without issue!

marky-d

[crankythunder]

Well, I went on facebook marketplace and found a divorcee who was selling her former husbands stuff really cheap.

Got a aluminum scuba tank that was certified in 2020 (the only certification on it) for $100.00. She said it was completely filled too!