Gusher Infection question

So question about the gusher bug. I think my "Bourbon Barrel" stout might have it.

I made a partial mash imperial stout a while back. It spent about 12 days in Primary, maybe 13 I'm fuzzy on the details. Then I put it into secondary along with some bourbon soaked wood chips, they'd been sitting in my freezer for the 12 days that the beer was in Primary, maybe a few more. I let that sit for 4 weeks, mainly to blend the flavor of the bourbon wood chips into the stout.

Then I bottled. I put in the amount of corn sugar that the online calculator I found here said that I should use for 2.2 volumes of CO2, which is on the higher side for the style but I like it that way.

I opened a bottle a month later and, while still green, it tasted fine. I did start giving a couple bottles away and heard no complaints.

Recently however, I've cracked open 3 in the past week and all of them have gushed. They still taste fine.

I typically soak the bottles in Oxyclean the night before, rinse and soak them in star san day off. I might have skipped the Oxyclean soak the night before, but I know for a fact I soaked all of them for at least 2-3 minutes in star san before bottling. I didn't have my bottling wand so I did have to resort to the spigot on my bottling bucket, but the amount doesn't vary that much. Gap is at least 1 finger, typically 2 from the top of the bottle. And yes I soaked the bottling bucket in star san (that's where the bottles actually got soaked.) Honestly, the only difference I can think of is that I had my wife helping me bottle, it was her first time... maybe she sneezed in it when I wasn't looking?

Additionally there is a ring on the bottle neck of quite a few, but no film, it honestly looks like the ring on a carboy after primary fermentation is done.

What I have noticed is if I freeze the bottles for an hour and then pop them in the fridge I don't get the gusher, but they do seem slightly more carbonated then I would expect.

Thoughts? I'd planned on unveiling this as a center piece beer for my 30th bday beer dinner party... but well would rather not serve something that's going to gush everywhere and/or make folks there sick. I haven't noticed any adverse affects from the few I've drank this week to check but... anyway figured I'd poll the collected wisdom here.

Did you chill your bottled beer before cracking them open? What was your FG reading before bottling? I see that you referenced an online calculator for the corn sugar measurement. How much corn sugar did you use specifically, and what was the batch size?

Many say the ring in the bottle neck is a dead give away. Many disagree. I have had the gusher bug and I've always seen the ring.

Anyways, how long has it been bottled? These things tend to only get worse with age so I would hurry up and drink the beer up while it still tastes good. You may want to look into replacing some of your tubing used in bottling.

The ring is a sign of krausen from some additional fermentation in the bottle. Additional fermentation will produce more CO2 and more pressure in the bottle. When you make the bottles colder, the beer can accept more CO2 so you get higher carbonation without gushing since the extra pressure is in the liquid instead of the airspace in the bottle. It's unlikely to get worse but the bottles may blow if they get warm after being cold.

How does the beer taste? Anything unusual or especially sour?

My OG was 1.082 and FG was 1.029

That being said I took it at bottling time, I meant to take a sample going into secondary so I'm not sure if the wood chips added additional unfermentables, anyone got some research on that?

The beer tastes fine, mostly you get the wood flavor, the bourbon part is fairly faint but present if you're looking for it, it finishes rather malty.

I had chilled the previous gusher bottles, but only for like an hour or two before drinking. Nothing like the freezing for an hour than into the fridge for several more before drinking that I've been doing.

I had added just shy of 4 ozs (I had to redo the calculations since I didn't write down what I added and entering all of what I knew to be true from my notes I would have put in 3.75 ozs)

The one other thing that occurs to me as worth noting is that the temperature in my apartment varies wildly throughout the day and week. I'm in the Bay Area and so one day this time of year the temperature might be in the mid forties and the next low 70's. My apartment tends to hang around the mid 60's low 70's but sometimes gets rather hot since I'm on the top floor of a 3 story apartment building.

At 1.029, I would imagine it wasn't done fermenting. You said it was 2 weeks in the primary and 4 in the secondary, so that was enough time but your gravity leads me to believe maybe it is fermenting more in the bottle.

What bknifefight said sounds right, either you had a really low attenuating yeast, or it wasn't finished yet.

Did you use a kit? Did it say what the FG should be?

It wasn't a kit recipe, it was one that I'd worked out on my own, but based on Calculations FG should have been 1.025 so it did finish 4 points higher than it should have. Maybe that is it and the ring is just refermentation... I figured that since I'd forgotten to check gravity before racking to secondary that the wood chips had added additional unfermentables.

Assuming that it is refermentation am I looking at bottle bombs given the lower corn sugar? Or simply a case of I need to freeze it to knock the yeast out and lower the temperature so excess CO2 gets absorbed?