Any Prism2 BMCL users? Opinion?

[telemonster]

Thinking about getting the BMCL kit for my Prism2 early next year. Anyone switch to one? Any opinions?

WOB good or bad?

Does the wing push up against the CL restricting it?

More difficult to clean out the CL when they aren't easily removable?

Not that I have ever needed to, but draining them while on a dive?

Less flood resistance?

Are the Hollis kits made by Subgravity?

 

[RVBldr]

Couple answers...
- Haven't noticed a WOB diff in moving from FMCLs. So far, happy with them.
- No, wing has no impact that I've noticed.
- Get the dump valves on each lung, no issues in flush and sanitize without removing BMCLs.
- never had to drain on a dive.
- Seems a bit more difficult to push the condensation into the lung to relieve the gurgling, but no issues with flooding either.

 

[211ratsbud]

Couple answers...
- Haven't noticed a WOB diff in moving from FMCLs. So far, happy with them.
- No, wing has no impact that I've noticed.
- Get the dump valves on each lung, no issues in flush and sanitize without removing BMCLs.
- never had to drain on a dive.
- Seems a bit more difficult to push the condensation into the lung to relieve the gurgling, but no issues with flooding either.

This is my experience.

 

[Brad_Horn]

Thinking about getting the BMCL kit for my Prism2 early next year. Anyone switch to one? Any opinions?

WOB good or bad?

Does the wing push up against the CL restricting it?

Based on the testing that Hollis published the WOB of the 2019 P2 is functionally the same with FMCL or BMCL at 1.56 J/L at 75lpm on Air at 40m when Horizontal on the set and increasing for both FMCL and BMCL to 1.67J/L at 75lpm on Air at 40m when Vertical; with Hollis DSV. With Hollis BOV it increases to 1.90 J/L at 75lpm on Air at 40m when Horizontal; leading to a likely extrapolation of 2.0J/L - with the BOV fitted - when Vertical.

Clever observation about the wing, with it fouling the BMCL by design, as this was captured in their test reporting:
" QQ-1900385-HollisPrism-v1-1
1.3 Rear-mounted counterlung configuration
It was noted that the movement of the rear-mounted counterlungs during ventilation could be restricted by the position of the wing buoyancy compensator (WBC), particularly if inflated. It was also of concern that the function of the exhalation counterlung variable exhaust valve (VEV) could also be compromised.

Therefore, to ensure that any influence was kept to a minimum, the WBC was never inflated during testing."

Not seen reporting of the various changes made to CLs and fittings since Hollis published their 2019 QinetiQ testing so new units may differ but are unlikely to have lower WOB as they would have announced this.

For comparison the 2012 P2 tested with reference LSTF-0916-20120413_095648 had a WOB of 1.85 J/L at 75lpm on Air at 40m with DSV.

 

[TuckerIdaho]

My P2 came with FMCL. I tried it on once and hated it. BMCL since first dive.

 

[slimshady]

I had a P2 with bmcl. I didn't find any WOB issues. The lungs are SG but the fittings are not compatible. Too bad since the SG lungs have zippers for easy removal for cleaning. I liked the P2,but the shop went out of business. I tried the KISS SW, but did not like the right can getting soaked. I use an XCCR now, 300 hours, and so far it's bullet proof.

 

[OTF]

Thinking about getting the BMCL kit for my Prism2 early next year. Anyone switch to one? Any opinions?

They're good, they work, I have no FMCL experience but trusted peers who have dived both seem to strongly prefer the BMCL.

WOB good or bad?

good to great

Does the wing push up against the CL restricting it?

No. The wing is behind/above the BMCL.

More difficult to clean out the CL when they aren't easily removable?

No. You just unscrew the loop hoses from where they enter the head, lift the hose ends up and pour half a scrubber bucket of steramine water into each, then lift the mouthpiece to pour everything into the lungs and drain from the pull dumps. Maybe a small splash of steramine into the head connections, without soaking the cells. This sanitizes the whole loop. I also disconnect the hoses from the BOV/DSV to let them dry out but some leave those connections attached all the time and just open the valve.

Not that I have ever needed to, but draining them while on a dive?

Drainable, not sure how it compares to fmcl

Less flood resistance?

Not sure if the FMCL is better, but this unit and setup is generally considered to have excellent flood tolerance

Are the Hollis kits made by Subgravity?

Don't know.

If you're getting P2 BMCLs make sure the internal bladders are the newer tougher black material not the old thinner translucent material.

 

[OTF]

I had a P2 with bmcl. I didn't find any WOB issues. The lungs are SG but the fittings are not compatible. Too bad since the SG lungs have zippers for easy removal for cleaning. I liked the P2,but the shop went out of business. I tried the KISS SW, but did not like the right can getting soaked. I use an XCCR now, 300 hours, and so far it's bullet proof.

As an XCCR-curious prism diver I'd like to hear your opinion on these two units. What do you like on the X, anything you prefer about the prism?

 

[slimshady]

As an XCCR-curious prism diver I'd like to hear your opinion on these two units. What do you like on the X, anything you prefer about the prism?

P2 is less robust than the X. Scrubber is plastic and the lid gets hard to screw on unless it's super clean. Cover easy to scratch and mine cracked from the first time I laid it down. It also popped off in a cave before I velcroed it on. I agree with your comment about getting the new black counterlungs. I popped one of the translucent ones during a pre dive check. I liked the P2 weight. The xccr is a little heavier by maybe 5 pounds.

The xccr is built up from a hammerhead with shearwater electronics. Easy connections to head and bov. Delrin can on mine but you can get aluminum. Stainless steel 8 pound scuubber so easy to pack. Nice wob too. Nice shrimp bov. I hated the adv and removed it. I have a qc6 on the dil side for off board. Sub Gravity has been great for service and Divetronics can service and repair the head and shearwaters if needed.

The x is a Mercedes and the P2 is a Chevy as far as build quality.

 

[Akcharger]

I like my BMCL, but it's all Ive ever known