Force carbonating with 8g co2

I'm looking at buying a pressure barrel some time to compliment my bottle collection. I'd like to finish the whole cycle of the beer and then transfer it to the keg and force carbonate. I've been looking at some idea's for starters. I've been thinking about getting a plastic pressure barrel and using 8g co2 disposable bulbs.

Will one bulb carbonate 40pints of beer? Will it be ok to attach the 8g bulb strait onto a full barrel of beer? (I'm a little worried about eccessive pressure due to the fact that the 8g bulbs dispense all their co2 at once)

If you have any other advice for a starter kegger, it's welcome.

Why not prime with corn sugar/DME and use those bulbs just for serving?

Isn't there a chance of the barrel/cap bursting if I naturally carbonate and force carbonate?

No, the_bird is saying do NOT force carb. use DME or sugar to carb, and the 8g CO2 to dispense. that's what those bulbs are good for is pushing beer out of a keg.

I think I read you get about 25 corny kegs off a 5lb CO2 cylinder. 5lbs = 80 oz of CO2. its 28grams to an ounce...so 3.5 8g bulbs to equal an ounce, or 280 bulbs to equal a 5lb cylinder.

so bulbs aren't real cost effective for force carbing a keg, but work great for dispensing.

Oh........