I just bottled 1 case of cream ale. (The other half went into the kegerator). I had a little left
over after bottling so I put the last 12 ounces into a 1 liter plastic bottle. I screwed the cap
on tight.
I thought I read that this plastic bottle will swell as it carbonates , telling me when to try the
bottled beer.
Not 100% sure if it will explode, I am sure that it depends on how much sugar you added to ferment. What I have read is that when you are doing this, you squeeze the bottle first to remove air and leave space for the bottle to expand.
I read something once on a beer forum about a guy “experimenting” with a plastic soda bottle. He filled it half full of corn syrup and half full of a yeast cake or something like that. Needless to say, he came home one day and the bottle had expanded to something resembling a balloon and had exploded the next day. I’m skeptical as to whether or not this actually happened but I would like to think it did. So in short; you’ll probably be ok with a little beer.