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2 Litre Plastic Pop Bottles?
this is my first day in this forum, but i have brewed a few batchs. my very first batch, i bottled in 2 liter plastin bottles. they worked like a charm i used 2 teaspoons of sugar to carbonate each, and they seamed to be just fine. i agree, they are not a long term plan, but they do work nice still for the extra liters of beer that dont fit into your carboy, or keg. im kinda a beer pig, so getting rid of 2 - 4 liters of beer in a day isnt a problem. just my ecperiance so far, and nice to find another friendly forum. 
It's a moot point if you can't seal them properly, but if you were taking them to a party or something, the 2 litre plastic bottles would be fairly light weight, they wouldn't break, plus when you were finished you could collapse them and recycle them.
Take them camping!
I have been experimenting with using plastic for bottling beer. Some bottles leak and some do not leak. The original Red Rubber Grolsch Gaskets are 1” in diameter and fit well in the plastic caps. I find that this gasket fixes the plastic bottle leak problem.
I just ordered 100 from http://www.homebrewit.com/contact for $4.95 plus shipping.
HI,all - I can tell you that i've been brewing in 2-litre plastic pop bottles here in the UK with standard coke /lemonade bottles for several years and have NEVER had any problems with beer contamination;loss of pressure or bottles bursting (plastic "flexes" with the pressure?).I clean/sterilize them with standard stuff before filling them(siphoning) from the brew bucket.Ive also re-used them again occasionally with no problems.I definitely find them convenient,as with 3 kids running around i've always got a steady stream of pop bottle supplies at hand.Its also handy to chill a bottle in the fridge for icy refreshment!
Plastic pop bottles.......can you use them and do they leave your beer flat and explode and smell like skunk..........well to answer those questions.......I use the 20 Oz. brown A&W Root Beer bottles to test my first couple of beers in. 1. You can tell if your young beer is carbonating....the plastic bottle gets hard. 2. Lids They sell replacement lids for about $5 bucks for 24 and I've used several bottle lids 4 or 5 times. 3. Light struck....If you use the root beer bottles they are brown....don't confuse commercial beers in clear bottles with being light struck....a lot of them have chemical compounds in them that prevents skunking....4. oxidation....if your pop was oxidated you wouldn't drink it either....I've kept the plastic ones around for several months with no noticeable effects 5. Will the lids hold....if the plastic blows up be glad it wasn't glass!!! 6. Sanitation just rinse them out real good and don't scratch them with a bottle brush, sanitize as usual and it will be fine!!!........last of all I always bottle one or two in plastic to keep an eye on carbonation and to have a portable bottle or two that I can get rid of to a friend....they tend not to bring your good glass bottles back....and now you don't have to ask them to.
GOODBREWING