There are lots of posts on the web about how to fill bottles from a keg of beer.  The most popular gear heady way to do it is to buy a counter pressure bottle filler or use a beer gun.  The beer gun seems a little easy to use.

However, I only bottle the occasional 6-pack or so from the keg and I’d rather spend my money on malt and hops than a beer gun.  What follows is a short step-by-step of how I fill bottles from my keg with stuff I have around the brewery.

Filling from a Keg:

1. Keg of beer must be chilled and carbonated.  I like to over carbonate by a few tenths (0.2) of a volume of CO2 to compensate for lost CO2.  (some of that lost CO2 is a good thing as I’ll state later)
2. I use a black Cobra/Picnic tap to dispense the beer from.  I modify the tap into a filler by using a piece of tubing that will stick right over the spout of the tap (usually 3/8 ID tubing).  The length of the tubing need only be long enough to reach the bottle of the bottle.
3. I chill down the bottles I plan to fill.  This reduces CO2 loss and foaming.
4. Right before I am ready to bottle (bottles and caps washed and sanitized), I dial down the CO2 on my regulator to zero PSI, then I burp the keg to release all the head pressure.
5. I put the tap with tubing filler into my first bottle and pull the trigger.  Then I slowly dial up the regulator until I have just enough pressure to get the beer flowing at a decent rate.  But not too fast to get excessive foaming.  This can be a little tricky to manage the regulator and the bottle filler at the same time.  But once you get the pressure set and the beer flowing; that’s it with fussing over the regulator settings.
6. Fill the rest of my bottles and cap them.  Getting a little foam while filling is a good thing as it helps to purge out the ambient air and O2.  This minimizes oxidation of the beer after bottling.
7. Once all the bottles are filled I reset the pressure on the regulator to my normal carbonating and dispensing pressure to keep the beer from going flat.

This method works good for all sizes of bottles just as long as your tubing reaches the bottom of the bottle.  And it’s certainly cheaper than purchasing a beer gun.