How Much Raspberry Puree for a Chocolate Raspberry Stout?

I'm getting ready to brew some beers for a wedding for friends in October. The first that I want to do is a chocolate raspberry stout, based on Jamil's Black Forest Stout in Brewing Classic Styles.

OG:1.071
FG: 1.018
IBU: 38
Color: 39 SRM
Alcohol: 7.6% ABV

13.9 lbs Maris Otter
0.75 lbs Black Roasted Barley (500L)
10 oz Crystal (40L)
10 oz Crystal (80L)
0.5 lbs Chocolate Malt (420L)

Kent Goldings 5% AA, 60 min

4 oz Cocoa Powder, 0 min

Wyeast 1028 London Ale

So after it's most of the way fermented, I plan to rack it over to secondary, and add 2oz of cocoa nibs and the raspberries. The original recipe calls for 6lbs cherries and 8 oz cocoa powder, but no nibs. I'm thinking 6 lbs of raspberry puree is going to be way too much. Should I be looking at 4 lbs?

I want to use the cocoa nibs in secondary because while I've been happy with cocoa powder before, I want to give nibs a shot for the more natural flavor. Does the 2oz in secondary sound like enough?

I'm brewing this over the weekend, but the wedding isn't until the second week of October, so it's going to age for awhile.

tl;dr: Is 4 lbs of raspberries, and 2oz of cocoa nibs in secondary, plus 4 oz cocoa powder in the boil going to give me a good quality chocolate raspberry stout?

I have never used chocolate or raspberries. (except for flavor extract) I think this beer is too extreme for the average wedding though, unless half the people there are beer connoisseurs or home brewers. I would brew something much more conservative. I like the recipe idea though, as something I would like to make.

.......... bumping this thread

mrk305 said:

I think this beer is too extreme for the average wedding though, unless half the people there are beer connoisseurs or home brewers.

Click to expand...

Never fear. Half the attendees are beer connoisseurs, the rest are bourbon connoisseurs. It's gonna be one heck of a party!

I am quite curious to know how this turns out, as I had the same idea and would prefer not to have to tread new ground on this.

So did you use 4 lbs of raspberries and chocolate nibs? Have you tated this yet?