Originally Posted by LoadedFront
In Beer Smith, my efficiency came out to something like 40%. My temps tended to run a bit hot (160-165 rather than 155), and I may have been a bit shy on water. Any thoughts/input appreciated.
That would explain the poor efficiency. You want to have 1.25-2 quarts per pound of grain. Temperatures are also crucial. At over 160, you could very quickly denature the enzymes.
The other thing to keep in mind is that you want the same amount of base grain as other grains, to ensure conversion. With only 1 pound of base grain, and all the others specialty grains, you wouldn't be able to convert all of the sugars in the oats. With 4 pounds of specialty grains, you'd need 4 pounds of base malt to ensure good conversion.
The too-high temperature, combined with inadequate enzymes, would be a big factor.