I used this calculator
http://www.geocities.com/lesjudith/Alcohol...Calculator.html
With the Figures of 4.00 Desired, 8 Deg Celicus, 23 Ltrs and Corn Sugar. It came to 250gm which I thought was a bit much, so I reduced it to 225gm. Which is about 3.7 Desired.
No exploding bottles yet after 3 weeks in bottles.
Might just put this one to the side, and try something else!
FWIW, I just bulk primed an American Wheat+W3056 using the same calc. and the figures:
2.4 C02 desired, 18C, 21L, DME 70 AA% for 227g required.
After 4 weeks in bottles, it's carbed up beautifully with a clean, creamy head and good head retention.
I shot a photo to demonstrate the amount of bottling I did in one day (bloody hell, took nearly 7.5 hours!) I was about 1/2 way through a wheat (in glass approx. 7 mins?) at the time of shot:
My guess is that your bulk priming at 8C may not have allowed for your DME to mix properly with the beer. Did you boil the DME with a pint of water for 10 mins. and chill to 8C before adding it? Did you use a brewers paddle or comparable to gently stir in the priming? Additionally, It's a good idea to give it a light stir every dozen bottles or so (during the bottling process) to be sure an even mixture is shooting to each bottle.
In comparison to my batches, I would say:
-4.00 even 3.7 is too much C02
-Poor mix of priming and a low temp may mean you have some very over-carbed and some under-carbed
-Infection
Recipe, as may help:
True American Wheat
A ProMash Recipe Report
AHA Style and Style Guidelines
-------------------------------
06-C American-style Ale, American Wheat
Min OG: 1.030 Max OG: 1.050
Min IBU: 12 Max IBU: 17
Min Clr: 2 Max Clr: 8 Color in SRM, Lovibond
Recipe Specifics
----------------
Batch Size (L): 46.00 Wort Size (L): 46.00
Total Grain (kg): 8.54
Anticipated OG: 1.040 Plato: 9.94
Anticipated SRM: 3.0
Anticipated IBU: 13.8
Brewhouse Efficiency: 75 %
Wort Boil Time: 60 Minutes
Pre-Boil Amounts
---------------
Evaporation Rate: 5.00 Percent Per Hour
Pre-Boil Wort Size: 48.42 L
Pre-Boil Gravity: 1.038 SG 9.46 Plato
Formulas Used
-------------
Brewhouse Efficiency and Predicted Gravity based on Method #1, Potential Used.
Final Gravity Calculation Based on Points.
Hard Value of Sucrose applied. Value for recipe: 46.2100 ppppg
Yield Type used in Gravity Prediction: Coarse Grind As Is.
Color Formula Used: Morey
Hop IBU Formula Used: Rager
Grain/Extract/Sugar
% Amount Name Origin Potential SRM
-----------------------------------------------------------------------------
38.7 3.31 kg. Lager Malt(2-row) America 71.27 1
51.6 4.41 kg. Wheat Malt America 77.50 2
9.7 0.83 kg. Cara-Pils Dextrine Malt 67.12 2
Potential represented as Yield, Coarse Grind As Is.
Hops
Amount Name Form Alpha IBU Boil Time
-----------------------------------------------------------------------------
34.45 g. Hallertau Hersbrucker Whole 5.10 11.4 60 min.
8.61 g. Hallertau Hersbrucker Whole 5.10 1.5 30 min.
17.23 g. Fuggle Whole 4.20 0.9 10 min.
Yeast
-----
WYeast 3056 Bavarian Wheat
Mash Schedule
-------------
Mash Type: Multi Step
Grain kg: 8.54
Water Qts: 17.59 - Before Additional Infusions
Water L: 16.65 - Before Additional Infusions
L Water Per kg Grain: 1.95 - Before Additional Infusions
Acid Rest Temp : 0 Time: 0
Protein Rest Temp : 50 Time: 45
Intermediate Rest Temp : 0 Time: 0
Saccharification Rest Temp : 69 Time: 80
Mash-out Rest Temp : 74 Time: 5
Sparge Temp : 71 Time: 60
Total Mash Volume L: 22.35 - Dough-In Infusion Only
All temperature measurements are degrees Celsius.