I've seen some questions touching this topic, but didn't seem to get a definitive answer one way or the other, so here goes:
I drink a good bit of Diet Mountain Dew. The 6 packs I buy come in 24 oz. PETE plastic bottles. It seems to me that these bottles are built to withstand the same (if not greater) pressure as a beer will exert when fully carbed. If I don't store my bottles in a lighted area (who does, anyway?), what's the harm in using these bottles? I would only use them 1 time after I've had the Mountain Dew in them (I think I've seen that re-using the caps could be problematic), plus wouldn't it be a good indication about the relative carbonation of the beer, i.e., if it's tight and hard, it's carbed?
allow you to pressurize or forcecarbonate in those PET bottles if you have a ball lock keg system. A couple guys in my homebrew club use these to bring beer to parties. I throw a couple growlers in a cooler.
I have seen 1/2 L bottles of soda on the shelves at the grocery store (Pink is the new Black, and .5L is the new 20 oz... ). I have seen .5L PET bottles (empty) for sale at the LHBS. Brown, w/out caps.
The LHBS .5L bottles run from 80 cents to about a buck per bottle. The soda is on sale for the next month, and the .5L bottles cost 33 cents, with a cap. You have to remove your own labels. Now if I could only find a way to get rid of the Mtn Dew... ;-)
Seriously, I took some six packs in to work and offered them up for anyone to drink and return the empties... nobody wanted Mtn Dew. Dang, and those were the ones I wanted to put cider in. Oh well.
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Oh my gosh, but cider's neat.
Taste's so sweet, it can't be beat.
Good in the cold or in the heat.
Oh my gosh, but cider's neat!
I use 20oz, 1L and 2L PET soda bottles all the time. When I keg, I draw off the first beer into a 2L bottle. This catches that first bit of yeast and lets me do a force carb for a taste.
For Cinco De Mayo, I used six Diet Mt. Dew bottles to smuggle beer around in public. Normally, I peel off the labels, but left those on for the disguise. They worked GREAT, and I'm going to use them again next week for camping.
I just set the CO2 to 5 psi and fill away. Zap them with the carbonator cap if needed.
To get the soda smell out, rinse them, then put in a little oxyclean, fill with warm water, and let them sit overnight, cap down (the most smell tends to be in the cap). Rinse well and you are ready to fill.