Need to reduce pressure at tap

I visited a little local West Australian cidery recently. Nick's cider pours into the glass with a beautifully fine froth on top, crystal clear, and streams of bubbles rising up inside.
He says that to get good carbonation I need to run 30psi from gas bottle to keg to tap.
Yet when I follow the carbonation charts the indicators are about 12psi for 2.5 volumes. I tried this but no matter what I do, the cider gushes into the glass with large bubbles that burst quickly, then the cider is almost flat.
Bleeding the gas from the head space helps but Nick does not do this.
I use 3 metres of 4mm internal diameter pvc tube to the tap.
Nick did have, though, a device in his line between keg and tap that may have been reducing his delivery pressure at the tap without bleeding the keg.
I have scoured the net and plumbing suppliers for such a device but unsuccessfully.
Does anyone know what this device may be?

Many thanks from Cliff in Western Australia. [email protected]

You need a flow restrictor, OR a very long run of 3/16" beverage tubing (like 30 feet). Both of those are only available from homebrew stores, and not in general plumbing.

Hi Yooper after much more research today I think I have found the problem. It may be that I have overcarbonated, which is causing the gas to come out of solution as it passes through the tube to the beer gun. It is evidenced by streams of bubbles showing in the tube as it flows. I was advised to take the keg out of the fridge and bleed off the headspace then shake it, bleed it until pretty well flat, then gas it up again but at much lower pressure. Hopefully this will solve my problem.

Fossil said:

Hi Yooper after much more research today I think I have found the problem. It may be that I have overcarbonated, which is causing the gas to come out of solution as it passes through the tube to the beer gun. It is evidenced by streams of bubbles showing in the tube as it flows. I was advised to take the keg out of the fridge and bleed off the headspace then shake it, bleed it until pretty well flat, then gas it up again but at much lower pressure. Hopefully this will solve my problem.

Click to expand...

It will, but it won't be as well carbed. If you want to serve it nicely carbed, you need more line and/or a restrictor plate.