How fast does gravity drop? Inaccurate hydro reading.

[Brainsnap]

I started brewing a beer yesterday, a spiced brown ale forsolstice festivities. I'm usually doing all-grain, but this time I went the extract approach to save some time.

The problem was, after mixing water with the wort (i had about 2 gallons left after a 3 gallon boil) i obviously couldn't take a very good gravity reading. I added the water directly to the carboy. The expected OG according to brewsmith for 5 gallons was about 1.065. My reading showed 1.104, which was clearly not the case (and yes, i tested my hydrometer for calibration).

I decided just to wait until the water was better mixed to test it, so I pitched two packets of s-04 and put the blowoff on. Approximately 16 hours after pitching, i took my gravity reading, which is now 1.056. The fermentation is going well and bubbling furiously, with a medium amount of krausen.

So my question is - 1) how do you mix the wort and water well enough to get a better original gravity reading?

and

2) How fast does gravity drop? I would like to estimate the actual OG I started with, instead of this bunk number I came up with. The beer probably started fermenting about 4-5 hours after pitching. I imagine it ferments at different rates according to the yeast used, but maybe there is a rule of thumb I don't know, or someone has a cool graph to help explain it?

Any help would be appreciated!

 

[flars]

Take your OG reading after aerating the wort. The aeration should result in a thorough mix.
The Brewsmith estimated OG should be reasonably close to use if the fermentables were entered correctly and volume in the fermentor is correct.
Fermentation times will vary. There are to many variables to chart a fermentation time.

 

[RM-MN]

1. It's extract, you can rely on the maltsters numbers and calculate the OG from there. It will be quite close to the 1.o65 depending on how good measurement of the volume was.

2. Depends on the yeast, the temperature, the phase of the moon, the attitude of your girlfriend.....Yeah, too many variables to get a decent estimate.

 

[Brainsnap]

I took the first reading, knew it was off, then sloshed around the fermenter pretty well to aerate it. that didn't seem to help it mix well enough, unfortunately.

i did double check all the settings on brewsmith, so I imagine that i am pretty close to what was expected, but thought there might be another way to go back and check it.

thanks for the help!

 

[billingsbrew]

I'm not sure how to get a better OG then just to mix it complete. As far as fermentation I have had a 1.105 barley wine falls to 1.020 using S04 in just two days.