CO2 Bottle Threshold Question

[Phreak]

Hey guys,

I'm going to be bottling a hefeweizen this weekend. I have an assortment of 500ml bottles to use for this. Now most of them are pretty thick but a have a bunch of Lezajsk bottles that I am wondering if it would be able to withstand the 3.5 volumes of CO2 I'm planning to use? Another bit of info is that my place is running at about 76-78 during these months, if that will have any effect on potential bottle bombs? I plan on 3 weeks or so in the bottles because of the size. Should I bottle with less CO2 volumes to avoid problems or has anyone had any experience bottling higher volumes in the Lezajsk bottles? Any help is appreciated. Thanks a bunch!

 

[Warthaug]

Shouldn't be an issue. Plastic pop bottles are designed to safely hold pressures of 60-80PSI (i.e. 3-4X the expected working pressure) and water-rocket hobbyists frequently pressurize them to 100+PSI with only rare failures. So the likelihood of catastrophic failure is pretty low at the 40-50PSI you may hit.

What I don't know about is whether the cap will maintain that pressure without leaks. The bottles are built to withstand higher pressures - whether the seals on the cap are upto par is another question.

Bryan

 

[Phreak]

Thanks, Bryan. That's some great info. Yeah, I just wasn't sure because the Lezajsk beer bottles felt lighter than the others so that's good to know. The caps I'm using I believe are just the run-of-the-mill crown caps I got from OBK: http://www.ontariobeerkegs.com/Bottle_Caps_Classic_Silver_Cap_for_your_Homebrew_p/bottlecaps.htm

So, hopefully they'll hold up. I'll give it a go and see what's what. :rockin:

 

[zachattack]

Shouldn't be an issue. Plastic pop bottles are designed to safely hold pressures of 60-80PSI (i.e. 3-4X the expected working pressure) and water-rocket hobbyists frequently pressurize them to 100+PSI with only rare failures. So the likelihood of catastrophic failure is pretty low at the 40-50PSI you may hit.

What I don't know about is whether the cap will maintain that pressure without leaks. The bottles are built to withstand higher pressures - whether the seals on the cap are upto par is another question.

Bryan

I disagree. Soda is very highly carbed (>3.5 volumes) which means that at 70 degrees the bottles are going to see 45 psi. I'm not sure how that corresponds to a 3-4x safety factor.

Purposely overpressurizing a glass or plastic bottle can be pretty dangerous, obviously many homebrewers have had bottle bombs and some have even been injured. It's never wise to exceed the pressure rating for any vessel, and for homebrewing it gets complicated because all the "ratings" are generally anecdotal. By that I mean that a bottle, growler etc. does not have a pressure rating stamped into it like a keg does. The general rule is that assuming you have normal ambient temperatures (meaning you aren't going to store the bottles long term in a 110 degree garage) you should not exceed 3 volumes of CO2 for standard beer bottles. For your thicker-walled ones you should be OK, and since soda is carbed higher than most beer you should be OK with plastic soda bottles as well.

If it were me, I'd bottle the remainder in plastic seltzer bottles instead of the regular (thinner) glass bottles, or else drop the carb level down a bit. But I tend to take safety pretty seriously.

 

[Warthaug]

Oops, I Lezaajsk was a kind of plastic pop bottle. I think glass bottles are built to similar specs, but you may want to call up OBK to see if they have more info.

B

 

[Phreak]

If it were me, I'd bottle the remainder in plastic seltzer bottles instead of the regular (thinner) glass bottles, or else drop the carb level down a bit. But I tend to take safety pretty seriously.

I'm with you on that one. I think I may just go with the lower carb level for this batch to be safe. Since Hefeweizen's have a carb level (from what I've read) of 3.5 - 4+ volumes, do you forsee any noticeable differences in taste dropping down a half volume to 3?