How many gravity points means bottle bombs?

[sawyera]

Hey all,

I just brewed a belgian saison with Wyeast 3724, which gave me quite a run for my money for a while. Finally, after a month and a half, got it from 1.060 to 1.011.

I'm brewing for my fraternity, and school's about to let out, so I didn't have much time to wait to confirm a steady finished fermentation. I took solace in the 79% attenuation, given that the high of their range, as listed on their site, is 80%.

I'm wondering, however, how wise this was. Hypothetically, if the beers had yet to go from 1.011 to 1.010, or 1.09... would that mean bottle bombs?

How much of a differential is enough for a bomb? I'm conditioning at room temp, probably 70/71˚F.

Thanks everyone,
Sawyer

 

[Qhrumphf]

I don't remember the exact number offhand and too lazy to look it up, but I think dropping 2 or 3 points in gravity equates to about 1 volume of CO2. So depending on how it was primed, if it were to drop from 1.011 to 1.005 (where I often have that yeast finish myself), you could definitely be in the danger zone. Gushers likely, bombs possible. I know most folks don't recommend pushing a standard 12oz longneck bottle much above 3 volumes, but exactly how far above that they start bursting I don't know off the top of my head.

 

[55x11]

3 gravity points is about 2 CO2 volumes, which is what most people carbonate at with sugar.

I would say 5-6 volumes is a "gusher" and beyond that, 6-10 volumes or so, you will get a pretty big risk of bottle explosions.

You could prime less with sugar if you think it is definitely going to drop a point or two or three.