High carbonation in PET Bottles

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noshadow

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I've currently got a Hefeweizen brewing away and will hopefully be bottling it this week. From what I've been told in another thread I should be aiming for 3.5 to 4.0 volumes CO2 which is a lot higher than any of the previous brews I've done.

I understand that this can cause bottle bombs with glass bottles but will this cause issues with the Coopers PET bottles I use?
 

noshadow

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Anyone able to offer any insight on this? I'll be bottling in 3-4 days so would be good to know how far I can push it with priming sugar
 

TheOsprey

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I'm no expert, but I'd say that a bottle of Dr Pepper would have higher carbonation, and is fine in plastic bottles...
 

dwhite60

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Drop a chunk of dry ice in a plastic soda bottle with some water in it, screw on the lid and stand way back. You'll be amazed how much pressure a PET soda bottle can take. Videos on the internet. Video below with a hand pump claims 145 psi, 10 bar.

 
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Drunkula

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Coca Cola has 3.1 volumes of co2. Pet bottles can take insane pressure. The hydraulic press channel on youtube sometimes blows them up.

Just checked and they're rated to 150 psi. Rah!
 

Graz

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As above PET bottles are ideal for this. I've just bought a carbonation cap to make fizzy water at home and as it was the only PET bottle I had laying around I used a Coopers bottle to try it. The instructions said don't exceed 40 psi and it's slightly unnerving giving it CO2 at that pressure whilst shaking the bottle but not a problem. As mentioned they're good for much more than that.
 

BlackRegent

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I've currently got a Hefeweizen brewing away and will hopefully be bottling it this week. From what I've been told in another thread I should be aiming for 3.5 to 4.0 volumes CO2 which is a lot higher than any of the previous brews I've done.

I understand that this can cause bottle bombs with glass bottles but will this cause issues with the Coopers PET bottles I use?
I've recently done a raspberry wheat beer with a very high level of carbonation (I think I added 250g of corn sugar as a batch prime to a 23 litre batch). The PET bottles coped no problem. Also, if you purge the air by squeezing the bottles before screwing the caps on, you give the bottles a bit more to work with.
 

stan.distortion

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Once as I kid I wondered how much pressure a coke bottle could take, one drill bit, an old valve off an innertube and 20 minutes later I was getting frantic with a foot pump (and 40psi after I was knackererd). I put it on a compressor and hid around a corner not long after, 120 psi... I'd made a few of those, some of then got scratched almost to ribbons from jacking things up with them but none ever burst (milk tasted totally different out of them btw, extremely creamy). I've never seen the PET bottles but they look a lot thicker so if anything's going to blow it would be the threads on the cap imho.
 
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