Steel 72 vs HP100 weight difference

[Mtbr]

Does anyone know what's the buoyancy difference between a steel HP X7 100 vs. steel 72. I'm interested in both full and empty weigh difference.

Thanks!

 

[Bubbletrubble]

Does anyone know what's the buoyancy difference between a steel HP X7 100 vs. steel 72. I'm interested in both full and empty weigh difference.

Mtbr,

It depends on which steel 72 you're talking about.

The answer to your question can be found on the Tech Diving Limited Tank Specs webpage.

Enjoy.

 

[DA Aquamaster]

An X7-100 is about -1 when empty and about negative 8.5 when full, not counting the valve.

In theory, the generic 2250 psi steel 72 is also about -1 when empty and about 6 lbs negative when full but this includes the valve. It is theoretical as I have found that steel 72's can vary 1 to 2 lbs in terms of buoyancy traits depending on when they were made and who made them.

When you factor in the valve, the 2250 psi steel 72 is on average probably 1 to 2 lbs more bouyant than an X7-100.

They are however overall pretty well matched and I have sets of X7-100 doubles that I use along with doubled Steel 72's for shallower dives. Worst case a 4 lb v-weight evens out any differences.

 

[Mtbr]

Thanks Bubbletrubble & DA Aquamaster for responding!

This is the exact information I was looking for.
I had trouble sinking with a steel 72 2250 psi tank with 600 psi remaining. However, at 15 feet, I had no problem holding my 3 minute safety stop. With a slight kick down, I can again sink with 600 psi in the tank.

The X7 and same amount of weight, I can always sink down with 400-500 psi in the tank. So, the 72 is definitely 2 or 3 lbs. more buoyant.

 

[captain]

Thanks Bubbletrubble & DA Aquamaster for responding!

This is the exact information I was looking for.
I had trouble sinking with a steel 72 2250 psi tank with 600 psi remaining. However, at 15 feet, I had no problem holding my 3 minute safety stop. With a slight kick down, I can again sink with 600 psi in the tank.

The X7 and same amount of weight, I can always sink down with 400-500 psi in the tank. So, the 72 is definitely 2 or 3 lbs. more buoyant.

If you have trouble sinking a steel 72 with 600 psi it is not because of the tank, you just need another pound or two of lead.