Refractometer seems to be giving off readings... help?

[Jakkob]

My refractometer gave me an OG of 17.9 Brix and a FG of 7 Brix, giving me around 9.5-9.7% alcohol by volume.

It'd be nice to say that I balanced my beer so well that it tastes like a 7% abv beer but is close to ten, but I'm wondering if its more likely I'm running into some problem with my refractometer.

I made a 5.35 gallon batch of strong hefeweizen and added 10oz of honey at high krausen.

My grist was:
-5lbs 2-row
-5lbs German wheat malt
-14oz Crystal Malts

Yeast:
-Weihenstephan Yeast with a 1.21 Liter starter
-1 Package of Nottingham Ale Yeast (when I noticed my efficiency was so good--over 90%--I needed more yeast cells.)

I mashed around 2 hours, including a protein rest @ 25 minutes long.
Thanks for your help!

 

[day_trippr]

With the grain bill plus the honey in 5.35 gallons of wort I get an SG of 1.060 which is around 14.7 Brix. The 7 Brix at the end of fermentation would then translate to between 6.5% and 6.66% ABV, depending on which correction tool I used...

Cheers!

 

[Jakkob]

That seems more correct, how did you calculate the OG?

 

[day_trippr]

I banged all your numbers into Beersmith...

Cheers!