CAVE DIVING DOUBLES...Largest PRACTICAL sized tanks?

[junebug]

I am currently searching for another LP95 to band and manifold for caving here in N.Central FL.....
I currently have a set of 95's (LP)that I am using and would like at least one more set.
My delima is in whether or not to band a pair of HP131's....?
I have a matched pair with L/R modular valves and just don't know if they are really practicle, given their size, and being HP, I think I would still be packing roughly the same volume with my LP95's (2400psi) filled to 3500psi?
I am curious as to what most cavers think is the largest size tanks that are actually practicle for caving. I have dove with a team mate whom uses twin LP120's......they are BIG, but I like the volume they are capable of holding.
Any advice would be greatly apreciated.

 

[LiteHedded]

practical.
you want 104s/hp130s for cave diving IMO

 

[PfcAJ]

104/108/hp130 (all pretty much the same when you fill them to 3500) are great tanks for cave diving.

95s filled to 3500 have about 245cuft in them, while 104s (or whatever you wanna call them) filled to 3500 have about 280cuft in them. That's a pretty substantial difference, equal to about half of an al80.

 

[junebug]

Thanks for the speedy replies. That helps...
My only aprehensions with the 131's was the added length of the cylinders. They are actually spanking new bottles.
I am just @ 6' tall, so I should be able to manage the length I guess. I dive them sidemount as well as single at times. Weight is going to be a real factor as far as distance to entry is concerned though, as I only weigh around 160lb. I manage the 95's fairly well, but then ANY set of steel doubles is going to be a load @ the surface.....thanks guys.

 

[PfcAJ]

I think you'll be fine. I'm 5'6'', and I climb in and out of sink holes all the time with them in my back. If its an issue, work on some core strength exercises.

 

[Dive-aholic]

I can do the same dive in backmounted 85s or 108s. In 108s, the drag created increases my RMV quite a bit, so I end up breathing more to swim the same distance. More is not always better.

 

[LiteHedded]

hit the gym Rob

 

[PfcAJ]

you also need to consider the amount of reserve gas you have, and think about gas as it relates to time at depth.

You might get just as far on smaller tanks (or maybe not), but you certainly have less gas to deal with issues.

 

[Superlyte27]

Tanks too big, and you'll burn up whatever advantage they bring in volume by having to deal with the extra weight and size of the tanks.

 

[SuPrBuGmAn]

I dove HP130s from my entry into cavern/cave diving. They aren't too big. They're fine. The only reason I don't have them now is because I couldn't get them to trim out(I'm 5'10") greatly while diving wet and sidemount, and I was at the far end of my wings inflation(wet) while diving them.