Not quite a bottle bomb

Last night I opened a bottle of Robust porter and beer went everywhere (unfortunately some landed on my sons homework book )(try explaining that to the teacher). I racked it two weeks ago, so I realize it may be it bit early to open. I did not put it into the fridge to cool it first, but why would it foam over like that?

It kind of turned into a pretty cool experiement for my wife and I. We kept checking to see if other bottles would do the same. However, we had to stop after 4 bottles It was very tasty.

Thanks,
popscube

So it was just that one bottle? Either you had an infection localized in that bottle (which would make it taste weird...sour, dry, etc.), or you didn't stir the beer well enough when you were bottling, and a disproportionate amount of sugar got into that bottle.

No it did it in all four bottles. I took the bottles from different sections.

My theory: the beer had not fully fermented and when you bottled it with the additional sugar the yeast went crazy and over carbonated the beer. You have to bring the bottles down to almost freezing before opening them, this will ensure the minimum amount of foaming.

That is what we will try tonight. I have a couple in the fridge now, to see if it will "kill" some of the foaming. The alternative is just to have our lips ready and spit out the cap.

Also, would giving it more time help with this problem? Does the carbon begin to lesson over time?

You need to chill it down before opening it. Even if you warm it up again after that first chill there will be more CO2 in solution as it takes a while for it to come out of solution.

EDIT: I have had some bottles foam up a little, slowly when not chilled first and these were highly carbonated. I think it is a combination of this and probably and incomplete fermentation. Be careful and get them cold soon so if all the sugar is not fermented you won't have bombs.

what was the starting gravity?
what was the gravity at bottling?

you may only have gushers at 2 weeks....in 2 more weeks you *could* have exploding bottles. Not a guarantee, just a possibility.

If I have this right, beginning gravity was at 1.056 and final gravity was at 1.013. It seems to be in the range of the recipe.

Your finishing gravity seems right, so I don't think that is the problem.

As the others have said, chill your beer then open it.

How much priming sugar did you use? Its possible you over primed. This calculator says about 3 oz of corn sugar or 5 oz of DME is enough for a Robust Porter.

Ok, with those gravities, I retract my warning of bottle bombs. Sounds more like carbing hasn't fully absorbed, or priming sugar didn't get fully mixed so a few are gushers and most won't be.

give it another week