"air" space above beer in bottle, how big?

Hello fellow brewers,
regardless of how we bottle, how much distance should there be between top of beer and crown cork or stopper. Intuition tells me that if it is too small, pressure could build too high and burst the bottle. I tend to leave 2 inches.
thanks

I've always used a bottle filler which, when you fill to the top, leaves exactly the right amount of space once you pull the filler out. You are correct that too small a space or too large a space can cause various carbonation issues.

The bottle fillers work great like jadeddog said, make sure you take it apart and clean it though, I ruined a batch to the gusher bug thanks to that

It works out to being about 1 1/4 inches with the bottle wand thingy...you'll have to translate it into UK measurement...you know centipedes or whatever you call it

I've always heard 1 inch, but that said, I've done more on individual bottles (when the last bit in the bottling bucket couldn't quite fill the last bottle) and it was fine.

Revvy said:

It works out to being about 1 1/4 inches with the bottle wand thingy...you'll have to translate it into UK measurement...you know centipedes or whatever you call it

Click to expand...

Well they used to call it inches too, then they succumbed to the EU and all their standardization nonsense.

Revvy said:

you'll have to translate it into UK measurement...you know centipedes or whatever you call it

Click to expand...

Don't listen to him, Bob. There are a few of us Yanks who like the metric system. (You know, because of how much more SENSE IT MAKES!)

My first batch I had a lot more head space then I should but my beer came out very very carbonated - https://www.homebrewtalk.com/f35/coopers-carbonation-drops-pic-review-87589/

John Palmer's "How To Brew" says 3/4".

How to Brew - By John Palmer - Bottle Filling

That's about what I did on my first two batches.

Someone got their bottling wand, some water a bottle and a ruler and wanna measure it?

I swear I did and it was about 1 1/4"

Yeah, I started doing the "fill with wand them remove" but instinctually didn't like the high headroom. ('cos I know what i'm doing )

I also rationalized I'd rather have one less bottle than more but slightly emptier. Ya see you have to leave the last bit for sediment as you know and I figured that was one less 1/4" of beer to throw away. Did I mention I'm a Scotsman?

If Revvy says he fills to the brim with the wand then pulls the wand and doesn't top off then that's what I'll do next time.

+1 on the bottle wand theory. Another thing I do is that as I fill each bottle, I just place a cap on the top. When I'm all done bottling, then I "cap" them. My reasoning for this is that in the 15 minutes or so between filling the bottle and securing the cap, some CO2 is given off, and drives off a small amount of oxygen in the headspace. I know that the amount of CO2 given off is miniscule, but it does create that protective "blanket" over the beer in the bottle.

telemarc said:

+1 on the bottle wand theory. Another thing I do is that as I fill each bottle, I just place a cap on the top. When I'm all done bottling, then I "cap" them. My reasoning for this is that in the 15 minutes or so between filling the bottle and securing the cap, some CO2 is given off, and drives off a small amount of oxygen in the headspace. I know that the amount of CO2 given off is miniscule, but it does create that protective "blanket" over the beer in the bottle.

Click to expand...

Plus they make really cool sounds when the caps pop up & down to release the pressure build-up...It's like they're alive

Well, I measure some of my bottle wand filled bottles and I was correct, the bottle wand leaves 1 1/4" headspace.

I measured a bottle of founder's Centennial IPA...and THEIR Headspace is 1 1/2"

So, I'll leave it up to you do decide what to do....

Me, I'm sticking with my bottling wand.

Many thanks, friends. A lot of speedy replies and some humour. The prize is awarded to the poster who thinks in the UK we measure length in centipedes. That is completely stupid, because you could never get 100 millipedes in a centipede. Off topic, did you hear that the EU has removed its ban on the sale of mis-shapen, too big, too small fruit and vegetables, apparently 18% of all EU production was thrown away because of this, and with people starving, too. The final laugh is dirty celery commands a higher price than clean washed and wrapped celery.

1 to 1.25 inches.

If you under-fill you increase your chances of having bottles explode. From my experience over-filling does not leave you open to beer grenades.

Whatever you do....don't underfill. W/ my very 1st brew...I filled a 22oz bottle less than half way...when I went to open it, I almost lost an eye. SWMBO = very very angry. Thank god she said.."here, open this for me"

Is this all about bottling after secondary or bottling straight from primary? I'm bottling into 2 litre plastic coke bottles from secondary and am not getting too much extra pressure build up.

So is there a downside to leaving LESS headspace in bottles?

Revvy said:

Well, I measure some of my bottle wand filled bottles and I was correct, the bottle wand leaves 1 1/4" headspace.

I measured a bottle of founder's Centennial IPA...and THEIR Headspace is 1 1/2"

Click to expand...

Obviously you realize I wasn't disagreeing with you sir, just saying what Palmer has in his book. I could trawl through my 400+ posts of nonsense but I think it's safe to say I haven't disagreed with you yet.

FWIW, Palmer's book is very good but some of his math and chemistry is flaky.

I've filled bottles up to the brim and the only downside is that it took 3 months to carb.