Life expectancy of 7oz C02 tank

[Swedgin!!]

What’s the life expectancy of an aluminum 7oz co2 tank? The ones I have are old old. Ones dated 4-88 and the other 4-90 ( I believe those are dates) They both are stamped:
DOT E7737-1800
CLIFFDIV
The chances of me using them are real slim. I’m taking a break from work and thought, Why not ask the experts. 🍻

[Drcemento]

I believe there is no stated life expectancy. I have a few of those really nice brushed finished black anno'd CIFFdev ones. re-valved them with new valves and they are in service still for my C02 loving guns. The valves are the weak point, but simple and cheep to replace. If the tank is dinged or dented in any way i toss it I also look with a flashlight for any corrosion or funk inside. if your really in doubt and want assurance hydro it.

[Swedgin!!]

The tanks I have are still in good shape with no dents. I think there’s a little scratch on one of them but that’s it. I know one of the valves has a brass Cooper-T on/off and the other is standard. If I end up changing the valves out I’ll look inside to see what the condition is like. Maybe get it tested down the road sometime.

[XEMON]

Those should fall under the "testing tanks" regulation (under 2" in diameter).
No hydro, no expiration 👍
*but* the field can refuse to fill it or not want you to use them

If you dig into the DOT regulation you should find the fine print under the number stamped on the tank

PS1: DOT is expecting those tanks to remain empty unless they are currently being used, but i don't think that was ever challenged un court
PS2: this is in the US, each country has their own rules
PS3: im a rando online, this is by no mean legal advice ...

[Drcemento]

If you can find the seals, valves can be re-built just fine as well. just take everything apart and inspect it.

am I remiss in understanding that that DOT regulation, by law only relates to the transport of tanks? but was adapted by field insurers as a guideline for fields to follow to stay insured?

[XEMON]

Transport and storage of the tanks 👍
Insurance (and courts) usually rely on the the government agency for their rules, takes liability and burden of proof away from them. Why pay an expert and be liable when the DOT hands over the data for free?
But fields usually retain final say, they can take the liability to go against DOT guidelines, or refuse to fill an acceptable tank if they don't feel like it ...
I've had chromoly tanks turned away in the past, even then they are totally acceptable according to DOT guidelines. Also had field only feeling at 75% "for safety reasons" ...

[Chappy]

7oz4Lyf

[Kit352]

I have a bunch from the 80s I use. If they get grungy looking I give them a quick rub down with scotch Brite and hit them with some spray paint so no one has a reason to refuse filling them. I do need to replace the valve seal every 10 years or so. Upgrading them to an on off valve is a good idea so you can test to seal by quickly flipping the knob.

[Frmrspec]

What’s the life expectancy of an aluminum 7oz co2 tank? The ones I have are old old. Ones dated 4-88 and the other 4-90 ( I believe those are dates) They both are stamped:
DOT E7737-1800
CLIFFDIV
The chances of me using them are real slim. I’m taking a break from work and thought, Why not ask the experts. 🍻

just make sure they are not chrome moly tanks (you can usually tell by a rounded dome bottom and being significantly heavier than traditional C02).. those lost their certification ages ago and cannot be used any longer even if under 2”

[Swedgin!!]

The tanks are mos def aluminum. I did have a one of the steel tanks years ago but that got tossed. I do appreciate all the responses 🍻

[pneumagger]

just make sure they are not chrome moly tanks (you can usually tell by a rounded dome bottom and being significantly heavier than traditional C02).. those lost their certification ages ago and cannot be used any longer even if under 2”

Source for this info?