Bottle conditioning carbonation

[Gledison]

Hi everyone.
I would like to check with you regarding carbonation directly in the bottle.
I´m Aware of the recomended values for different beers as well the formulas needed to achieve the Targets.
Mostly i´m targeting a 2.5volumes of CO2 which requires ca. 2.2g of table sugar for a 330ml bottle.
I have a Manometer coupled to a 330 ml coke bottle which i use to follow the carbonation. At 20°C (68 °F) im getting at the end of 7 days conditioning ca. 4 bars (58 psi) of pressure. This value gives me a 8.2 g/L CO2 = ca 4 Volumes CO2.
Am im missing something here?
Acutally, im quite happy regarding the carbonation (head, mothfeel,etc). In my first brew i´ve used 2g of sugar and i missed some CO2, after that im keeping 2.2 and the outcome is good enough. However the values are not matching somehow. Am i just overcabonating and somehow enjoying it?
thanks for any comment

 

[illingwd]

All those calculations look right. If the beer has the right head and doesn't explode out of the bottle, are you sure your pressure reading is accurate? 4 volumes would be overcarbonated for almost any style I think.

 

[Gledison]

All those calculations look right. If the beer has the right head and doesn't explode out of the bottle, are you sure your pressure reading is accurate? 4 volumes would be overcarbonated for almost any style I think.

My manometer could be the Problem. I'm not sure. At least I'm following the common knowledge and adding the suggested amount of table sugar for a 2,5 Volumes. The main reason I have a control manometer is to be sure I'm getting carbonation

 

[jmcnamara]

forgive my ignorance, but does the manometer measure the co2 absorbed in the beer or just the amount in head space?
it takes a little while for the beer to take in all that gas

 

[Gledison]

forgive my ignorance, but does the manometer measure the co2 absorbed in the beer or just the amount in head space?
it takes a little while for the beer to take in all that gas

After equilibrium, it measures the total amount of pressure in the bottle. the pressure in the headspace is the same inside of the liquid. its all distribuited. By cooling down, CO2 will be more dissolved in the liquid, therefore a little less pressure will be measured in the manometer.
I believe my problem has to do with residual sugar. I have other batch and its measuring 2.5 bars.
I will keep tracking this one and see how it goes. the good thing is that I have mostly Grolsh bottles, so I can release the pressure if its too high
cheers

 

[Head First]

Hi everyone.
I would like to check with you regarding carbonation directly in the bottle.
I´m Aware of the recomended values for different beers as well the formulas needed to achieve the Targets.
Mostly i´m targeting a 2.5volumes of CO2 which requires ca. 2.2g of table sugar for a 330ml bottle.
I have a Manometer coupled to a 330 ml coke bottle which i use to follow the carbonation. At 20°C (68 °F) im getting at the end of 7 days conditioning ca. 4 bars (58 psi) of pressure. This value gives me a 8.2 g/L CO2 = ca 4 Volumes CO2.
Am im missing something here?
Acutally, im quite happy regarding the carbonation (head, mothfeel,etc). In my first brew i´ve used 2g of sugar and i missed some CO2, after that im keeping 2.2 and the outcome is good enough. However the values are not matching somehow. Am i just overcabonating and somehow enjoying it?
thanks for any comment

Are you calculating temperature into your equation? I force carb so am not working with sugar anymore but I know temperature served is the co2 vol you are looking for and there is a big difference between room temp and frig temp in volumes.

 

[Head First]

http://www.kegerators.com/carbonation-table.php
Sorry kind of a tiny screen shot. Here is the website.

 

[Gledison]

Are you calculating temperature into your equation? I force carb so am not working with sugar anymore but I know temperature served is the co2 vol you are looking for and there is a big difference between room temp and frig temp in volumes.

Yes, im calculating considering the temperature.
I think the only explanation is residual sugar. I have a new batch now and its around 2.6 bars. A bit high but still ok i believe..
thanks mate.