Happy New Year Steve
When converting/copying any recipe, we are, of course trying to determine the correct weight of malt and hops to use. Malt is pretty easy. All you really need are the percentages of malts used and the original gravity.
Nearly every single recipe you come across in the brewing world though lacks enough information to copy the hop bill accurately.
To copy/duplicate a hop bill of a recipe with some degree of accuracy, the following information is needed...
A. Time of the hop additions
B. Weight of the hop additions
C. Alpha acid percentage of the hop additions
D. The 'Volume of Ambient Wort - VAW' (in other words, the 'Volume at Flame-Out (VFO) once chilled.
E. What type of chilling was used and when it was employed.
That's the bare minimum and most recipes will not provide the above. Of secondary importance is how the wort was chilled but let's forget that one for now.
The numbers and times you have quoted above are not important for us BIAB'ers (assuming you are able to full-volume brew / simultaneously mash and sparge with all your water). Putting all the above together, what we need are...
The Seven Most Basic Keys for Scaling a Recipe (Most recipes do not provide this.)
1. Original gravity required.
2. Percentages of malts used (and preferably weights as well)
3. Time of the hop additions
4. Weight of the hop additions
5. Alpha acid percentage of the hop additions
6. The 'Volume of Ambient Wort - VAW' (in other words, the 'Volume at Flame-Out (VFO) once chilled.
7. What type of chilling was used and when it was employed.
Of course, mashing temperatures, yeast, fermentation times etc are also of utmost importance but these are generally irrelevant to scaling.
What You Need to Do
I don't have the book but just had a 'Look Inside' at Amazon. (Looks like a great book actually. I think the title probably does it a disservice). Unfortunately I couldn't get a look at any one recipe. If I was able to, I can often use information in the recipe and the BIABacus to make a good guess at number 6 above. VAW is missing form nearly all recipes. Number 7, I have never seen except in a BIABacus report so don't hold your breath for that info.
We may be able to come up with a simple formula but the first step will be if you can let us know what info above of 1 to 7 that the recipes do give?
If you have found the above
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