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Old 12-07-2012, 03:58 AM   #1
kpot2004
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Dec 2010
Flint, Michigan
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Brewed a oatmeal stout today with a target of of 1.064. Stopped fly sparging when I had 6.5 gallons pre-boil. Pre-boil gravity reading was 1.048. Boiled 65 minutes and ended up with almost exactly 5 gallons. My OG ended up being 1.070. Something doesn't seem right here.. 6.5x48 = 312/5 = 1.062, how did I end up with 1.070?

 
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Old 12-07-2012, 06:04 AM   #2
emprbasist
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Dec 2011
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Were you taking gravity readings with a refractometer or a hydrometer? If hydrometer, did you take both readings at room temp or close?

 
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Old 12-07-2012, 07:14 PM   #3
kpot2004
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Dec 2010
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Quote:
Originally Posted by emprbasist View Post
Were you taking gravity readings with a refractometer or a hydrometer? If hydrometer, did you take both readings at room temp or close?
Gravity readings were taken with a hydrometer. Pre-boil reading was temp corrected, post-boil reading was taken when wort had cooled to 65.

 
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Old 12-07-2012, 07:34 PM   #4
helibrewer
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Nov 2011
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Volume measurement errors?
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Old 12-07-2012, 07:53 PM   #5
kpot2004
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Dec 2010
Flint, Michigan
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Originally Posted by helibrewer View Post
Volume measurement errors?
I have a wooden dowel that I use so I get exactly 6.5 gallons pre-boil, and I used the gallon markings on the bucket and ended up almost right to the 5 gallon line, maybe like 4.8-4.9 gallons.

 
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Old 12-07-2012, 08:59 PM   #6
mcl
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Gravity readings were taken with a hydrometer. Pre-boil reading was temp corrected, post-boil reading was taken when wort had cooled to 65.
This is why. You can throw the temp corrections out the window if they get too far above the calibration point.

 
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