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Why expected ABV but unexpected gravities?

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Mechphisto

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So I got a 5 gal extract kit from my local HBS, an amber ale.
The only numbers it gave me was an expected ABV of 4.4 and a final expected gravity of 1.016.

I calculated that my OG should be about 1.050.

My actual OG was 1.044. And my final gravity is looking to be 1.012.
Which puts my ABV about 4.2%

So, the ABV is close enough to the expected ABV, but the gravities are all shifted lighter(?).
Why might that be? Especially for a kit that I expect has been tried and tested and exact recipe?
(Every ingredient except water was provided, I didn't substitute anything.)

Thanks for any feedback!
Liam
 

petrolSpice

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You may have measured incorrectly, measured at the wrong temperature, hydrometer may be off, or you added too much water. I suppose the extract could have also had less sugar than expected, this would be more likely with liquid then dry.
 
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Mechphisto

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You may have measured incorrectly, measured at the wrong temperature, hydrometer may be off, or you added too much water. I suppose the extract could have also had less sugar than expected, this would be more likely with liquid then dry.
Well, maybe temperature, then? Because everything was pre-measured and I'm using a fermentation pail with gallon markings so the water is exactly 5 gal.
The "sugar" was a liquid malt extract, and let me tell you, I got every little speck of that thick liquid out of the container and into the wort! LOL

So, temperature affects it, then? The instructions said ferment at 68-70F, and where it's at, the temp has been holding a pretty steady 68F.

Thanks for the feedback!
 

petrolSpice

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Hydrometers are calibrated at a specific temperature, it should say this temp on it or the packaging. It's commonly around 68F. If the wort is anything other than this temperature, you have to correct the reading because the density of water changes with temperature. If I'm +/- 5F from the calibration temp I don't worry about correcting. However when I'm measuring mash gravity at 150F then I definitely have to correct the reading.

http://www.brewersfriend.com/hydrometer-temp/
 

BikerMatt

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Coopers family secret amber ale? I was using the beer enhancer 1 kit, did a 22l batch instead of 23 and ended up with almost identical numbers with final ABV less than 4%.
 

Sadu

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I bought my latest Hydrometer from Aliexpress and it's calibrated to 16c instead of 20c like most are.

It actually makes a surprising amount of difference to the gravity reading. Now I always take the temperature when I take a reading and run it through this tool if it's more than a couple of degrees away from the calibration temperature.
http://www.brewersfriend.com/hydrometer-temp/

With extract batches the OG can be out if you don't stir super thoroughly after adding the extract. If you added the extract early in the boil then this might not apply, but if you added the extract at the end of the boil then my money is on the OG sample coming from a 'weak spot' and the FG being low due to a good fermentation.
 

GPP33

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You had too much water. It's simply diluted. Markings on buckets aren't exact. Don't stress it.
 

Northbank

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You had too much water. It's simply diluted. Markings on buckets aren't exact. Don't stress it.
Yup -- weigh out (seriously...) a gallon of water in something like a milk just, mark that sucker so you know what a gallon is for next time. Pour the water in your kettle --- I bet it is off a wee bit.

Also ... the first hydrometer I had was off .... :| Having 2-3 is never a bad thing, but test it out in some distilled water (and the right temp) and see where it sits.
 

IndyBlueprints

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I currently have 3 hydrometers. Each of them read different, to the scale of 3-4 points. I wouldn't worry too much about the exact numbers, as you really want to know the difference between starting and finishing gravities, which will tell you your ABV.
 

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