Cask only 2/3 full and I'm wanting to store for bottling...

[nicklawmusic]

I've racked a 70L of pale rye into a cask and the 2/3 is going to be bottled. It's currently in a second 9G ferkin. My intention was to bottle next week or the week after but I'm a little bit worried about the air in the remaining 1/3. The head brewer (where I make all this stuff on their mini-kit) suggested I add a little bit of priming sugar so that the yeast will give off some CO2 to blanket the beer.

I'm wondering:

1) Will this method be okay on future batches?

2) Should I invest in a few 4.5 pins to store the beer in intending to bottle (I physically can't bottle it the day it's transferred).

3) When I do come to bottle this batch, should I account for the CO2 already in the beer when priming. I added around 50g dextrose to 30L. I aim for a carbonation of 2.4 when bottling usually. How should I account for this?

Thanks.

 

[jwalk4]

You can try purging the head space with a CO2 charger.
http://www.northernbrewer.com/soda-keg-co2-charger
But I have heard that purging the headspace of O2 is a bit of a myth.

Otherwise I'd prime in the bottles with carb tabs or drops ASAP.

 

[nicklawmusic]

Thanks for responding. In the end, I spike to somebody in the end who suggested storing the beer in large jerry cans or drums, filled to the top, as there'd be no airspace; or in a corny keg if I wanted it under pressure.