Calculating ABV for DFH 120 Clone

Today is the great day in which the nearly two month long process of brewing this recipe comes to an end. I am having trouble calculating the ABV for my batch.

Here is what I do know:
1. As opposed to the Homebrew Chef's recipe calling for 10 gallons, I only brewed 5 gallons. All ingredients, except the yeast, were cut in half.
2. The OG for my batch was 1.084.
3. Beginning on day 5, when I added the second batch of yeast, I added 6 ounces of dextrose twice a day for two weeks, amounting to a total dextrose addition of 10.5 lbs.
4. At the time of bottling, the gravity was 1.000.

So, what's my ABV?

According to beersmith that's 1.164, meaning 21.8%abv.


_

INWarner413 said:

4. At the time of bottling, the gravity was 1.000.

Click to expand...

Wait, what? Shouldn't that be like 1.030 or something for a 120 minute clone?

Anyway, here's what I'd do:

1. Plug in your initial ingredients into Beersmith
2. Mess with the efficiency until you get a 1.084 OG for the "predicted" OG.
3. Add your sugar additions to the ingredients.
4. Take the predicted OG and transfer it to the "actual" OG
5. Type in your "actual" FG
6. ABV should be listed on the right under "actual ABV"

Your FG is wrong.

bknifefight said:

your fg is wrong.

Click to expand...

+1

I must admit, I was looking for something quite higher than 1.000, but after three different samples, it was the same number every time. I think I'm just going to call the batch 20-something ABV and call it a day.

with that amount of alcohol its going to have some residual sugar balanced with the alcohol to give an equal gravity to normal water. Its still certainly fermented out a long way though. Its going to be very dry though and I dont know what FG to expect but its certainly thin.

What yeast did you use? I recently did a similar brew that got all the way down to 1.010 from 1.12 using a WLP099/WLP013 combo, so I'm just curious how you got this kind of attenuation...

If it is truly that low of a FG, attenuation of this sort (100%) is not desirable, bmick. A big beer like this needs body to create balance in the final product.