Starter

[Centimeter]

I purchased several packets of prestige whisky yeast. As a means of making the yeast last a long time, I plan on using a starter with an initial inoculation of 1g yeast per liter of starter. I will be using a magnetic stirrer which should translate to a pitching rate of one liter per 7 gallon fermentation. My question is, do I need to make my starter the exact same as the ferment I plan to do? The idea of spending hours mashing a couple liters of starter seems a little much to me. I know that this is important for beer, but is it really all that necessary for whisky? Would it be all right if I just used sugar and yeast nutrients in the starter? From what I understand, there is a risk of shocking the yeast due to change in osmotic pressure, however it couldn't be more so than pitching dry yeast.

Also, I was using http://powersbrewery.home.comcast.net/~ ... lator.html" onclick="window.open(this.href);return false;" rel="nofollow to come up with a grain bill and I was a little surprised at how much grain it suggested. At first I was going to use ~10lbs of grain for each 7 gallon batch, however this calculator is recommending upwards of 15lbs to reach a SG of >1.06 (I plan on using 65% corn, 25% winter wheat, 10% barley). Does that sound right?