Wheat is very common for Vodka, however there are a few commercial distilleries that are making wheat whiskey.
Have a look at
http://www.dryflydistilling.com/ for a 100% wheat whiskey. If you were looking for more of a bourbon type whiskey then you would be looking for
http://www.bernheimwheatwhiskey.com/#/welcome. This is a personal favorite of mine. If you were looking to make a wheat whiskey here is a grain bill selection based on the 2.5lb grain - 1gallon water that you may want to have a play with.
Water to Grain Ratio Wheat Whiskey
US liquid Gallon 1 Mash Water (Lt)
Litre 3.75 7.5 15 20 25 30 40 50 60 80 100 120 150
pounds 2.2 - 2.5 Grain Amounts (Kg)
kilo 1.1 2.2 4.4 5.9 7.3 8.8 11.7 14.7 17.6 23.5 29.3 35.2 44.0
Grain Breakdown (Kg) Blend Ratio
Wheat 0.6 1.1 2.2 2.9 3.7 4.4 5.9 7.3 8.8 11.7 14.7 17.6 22.0 50%
Corn 0.3 0.7 1.3 1.8 2.2 2.6 3.5 4.4 5.3 7.0 8.8 10.6 13.2 30%
Barley 0.2 0.4 0.9 1.2 1.5 1.8 2.3 2.9 3.5 4.7 5.9 7.0 8.8 20%
If you paste these into a spreadsheet so that they line up it will make more sense
Example 20l of mash water would need 5.9kg grain and the blend ratio for that would be 2.9kg wheat, 1.8kg of corn and 1,2kg barley(malt).
I tend to spilt my barley to use as the starch converter for each, wheat and corn. I boil them both separately as wheat like a different PH to covert than corn.