Bottle bomb

[btbnl]

Hi all,

I've just experienced my first bottle bomb in my second batch of beer, and I'm trying to diagnose the cause and plan any next steps.

It is a 5.5 gallon batch of a Drake's 1500 pale ale clone. The original and final gravities were spot on (1.054 & 1.012). It sat for 3 weeks in the primary and was then racked to a secondary to dry hop for 5 days. It was primed in the bottling bucket with 4.7oz of table sugar, which was calculated for 5.5 gallons though in the end I only got 5 gallons (need to work on my racking). All of the bottles were soaked in a sodium percarbonate solution and scrubbed with a bottle-brush to clean, and then soaked in iodophor to sanitize. They were then pulled from the soaking bucket and set to drain upside down in a sanitized bottle rack (not the tree kind - only the bottle shoulders came onto contact with the rack). Once 24 bottles had been set in the drainer they were immediately filled via a bottling wand, starting with the first out the bucket. The bottles were then boxed and the boxes put in a closet in a hefty bag "just in case".

After a week in the bottle, I pulled a sampler - just to see how it was doing - which was delicious but as flat as I would have expected. The next day (when the temperature hit the mid-80s) one bottle from the same box as the one sampled exploded.

So it was somewhat overprimed and the temperature did jump 10 degrees, but adjacent bottles that were both drawn from the end of the bottling bucket were flat and a bomb respectively, and none of the other bottles that experience the heat blew.

Have I just got a one-off rogue bottle? I'd hate to have to re-bottle the whole batch.

Is likely a wild yeast? Where would that have slipped through my sanitation?

Thanks for any advice.

 

[invictusbrew]

From what I gather in your post I don't think it was a problem with your sanitizing. My guess would be that it was just a fluke thing: either you had a higher concentration of sugar in that bottle (without measuring out and putting the same amount of sugar in each bottle, we have no way of knowing if we're getting the same concentration in each one, just that its going to be close) or maybe there was a defect in the bottle itself. Maybe someone else will come by that reads your post and sees something I missed, but that's what I'd assume happened.

 

[Jlaw3000]

Eh, prolly a cracked bottle.

 

[JimRausch]

Can't fault your sanitation procedures!
My guess is one defective bottle, or perhaps your priming solution didn't get evenly mixed in the bottling bucket.

 

[Shakybones]

Are you sure that you mixed the beer with the sugar thoroughly? Simply racking onto a sugar solution doesn't ensure thorough mixing. That seems like the easiest explanation to me.