Consistent overcarbonation in bottles

I'm having consistent overcarbonation issues in bottles, and I'm wondering what the culprit might be. My process is as follows:

- Calculate sugar needed to carbonate to desired volume (I've been using NB's calculator, though I have tried others and had similar results: http://www.northernbrewer.com/priming-sugar-calculator/).
- Put sugar in just enough water to cover it, boil, cool (not to room temp, but substantially), then dump into bottling bucket
- Rack beer on top of sugar, then stir gently a couple of times to assure it's fully mixed.
- bottle.

I live in Texas and am living on a student budget so I keep my apartment fairly warm; generally around 80*. I correct for this on the priming sugar calculator. I've also tried correcting the temp to around 85 or 90 just in case it's particularly hot in the closet I'm storing beer in (yes, I know these are not ideal conditions, but they are fine for my purposes and I don't have the budget to do any better right now). I'm not getting uneven carbonation; all my beers seem to be pretty overcarbonated. And I do allow time for the CO2 to dissolve; I don't drink a homebrew unless it's been in the fridge for at least 24 hours.

Given all that, I feel like I'm handling every control point. But I'm obviously missing something. Any idea what?

How are you determining when to bottle?

I think you should change the variable in your equation that you have the most control over.
Try reducing your priming sugar a little on the next batch and see if that gets you to a better level of overall carbonation. Most calculators work on the basis of optimal conditions. You need to modify to suit the conditions you have to work with.

As a side note....are you sure your beers are done fermenting?

Yeah, forgot to add that. I am sure my beers are done fermenting on these. I'll try reducing my carbonation on the next batch - I'm bottling some cider today, so it'll be alright if I end up undercarbonating since it's not really a style with a well-defined carbonation guideline anyway.

I'd like to give this post a bump, as I have the same problem.

I'm aware of the typical reasons for overcarbonation: not done fermenting, too much sugar, etc. I just consistently have a lot of carbonation but otherwise the beer is good.

I have one thought. Does an underattenuated beer require less priming sugar? For instance, if have a beer that is estimated to be 1.010 FG and it finishes out at 1.020, that would mean there are more sugars left in the beer. Do some of these ferment at bottling in addition to priming sugar and result in a higher amount of carbonation? (Or are these sugars usually unfermentable types?)

I've never read anything about a higher FG affecting carbonation, but I've reduced the amount of priming sugar going into a recent pale ale which spent a month in the primary and I continue to get this problem.

thasnazzle - any updates? anything work for you?