# 2nd all grain

### Help Support Homebrew Talk:

#### thehawk

##### Member
Doing my 2nd all grain right now. Brewing Hobgoblin clone by Orfy. Hit mash temp of 154. Collected 7.25 gal in boil kettle. Pre boil grav of 1.049. Here is the grain bill. 10.5lbs Maris Otter, .5lbs Crystal 60, .5 lbs Carapils, .4lbs Chocolate. Trying to figure out efficency, I get 84% by the calculation I am using. Seems kind of high? what do some of you come up with?
Thanks JIM

#### freddyb

##### Well-Known Member
I get 79.6% by this method...

(7.25 x 49) / ((10.5 x 38)+(0.5 x 34)+(0.5 x 33)+(0.4 x 34)) which is 355.25/446.1 = .796 or 79.6

OP

#### thehawk

##### Member
Here is what i used. I got the malt values from the book Designing Great beers.

(7.25 x 49) / ((10.5 x 36)+(0.5 x 34)+(0.5 x 34)+(0.4 x 26)) which is 355.25/422.4 = .841
Thanks

#### freddyb

##### Well-Known Member
Your method is fine. Grain potential values are just estimates that can vary in reality. I grabbed values from the HBT Wiki "Malt Chart" here: Malts Chart - Home Brewing Wiki

Maybe you can check with the grain manufacturers to get a closer estimate for the potential?

Either way, that's good efficiency. Nice work.

OP

Thank You!