I'd add about 3 ounces of Black Patent malt in addition to the chocolate malt and crystal.. Black Patent's color is around 525 srm. I just plugged the recipe into promash and 3 oz really did the trick on the color.
Sam Adams Honey Porter
A ProMash Recipe Report
Recipe Specifics
----------------
Batch Size (Gal): 5.00 Wort Size (Gal): 5.00
Total Grain (Lbs): 11.44
Anticipated OG: 1.059 Plato: 14.47
Anticipated SRM: 23.7
Anticipated IBU: 32.2
Brewhouse Efficiency: 70 %
Wort Boil Time: 60 Minutes
Grain/Extract/Sugar
% Amount Name Origin Potential SRM
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87.4 10.00 lbs. Pale Malt(2-row) America 1.036 2
4.4 0.50 lbs. Crystal 90L America 1.033 90
2.2 0.25 lbs. Chocolate Malt Great Britain 1.034 475
1.7 0.19 lbs. Black Patent Malt America 1.028 525
4.4 0.50 lbs. Honey 1.042 0
Potential represented as SG per pound per gallon.
Hops
Amount Name Form Alpha IBU Boil Time
-----------------------------------------------------------------------------
1.50 oz. Fuggle Whole 5.00 32.2 60 min.
0.50 oz. Fuggle Whole 5.00 0.0 0 min.
Yeast
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WYeast 1098 British Ale
