Best way to use carbonater cap

As the title says, what is the best way to use a carb cap for a 2 liter soda bottle?

Is it best to carb the beer in there by putting co2 in and shaking or put already carbed beer rom the keg into the bottle and then hit it with some co2?

Also, how long will that beer stay carbed after opening? I assume it would be like a pitcher of beer and need to be drank soon after opening.

Have the beer already carbed put it in, pressurize with the co2. It's like opening a bottle of beer just in 2L form, unless you have a co2 attachment to repressurize after opening.

http://morebeer.com/view_product/18301//CO2_Injector_Ball_Lock

Warped04 said:

Have the beer already carbed put it in, pressurize with the co2. It's like opening a bottle of beer just in 2L form, unless you have a co2 attachment to repressurize after opening.

http://morebeer.com/view_product/18301//CO2_Injector_Ball_Lock

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I think I read somewhere to squeeze the bottle. I assume that is to get the o2 out before pressurizing.

I've never read that. You could purge the bottle with co2 after filling it up (filling up the bottle will push most of the air out). But it's not like you are storing it for weeks at a time. If you are just taking it down to the park, I wouldn't stress about it.

Warped04 said:

I've never read that. You could purge the bottle with co2 after filling it up (filling up the bottle will push most of the air out). But it's not like you are storing it for weeks at a time. If you are just taking it down to the park, I wouldn't stress about it.

Click to expand...

Yeah I think that might have been if you are carbing in the bottle. This will just be for bringing it places.