Will I over-carb if I add priming sugar AND CO2?

[IndyBlueprints]

I have about a 6 gallon batch. Most of it I want to go into my 5 gallon keg, the balance I want to bottle. I know how much priming sugar to use for a 6 gallon batch, but how much I have to bottle, I won't know exactly until they are in the bottle.

My question is this;
Will there be any downside to adding my priming sugar to the entire batch, putting what I can in the keg, and then bottling the rest?

 

[McKnuckle]

Should be fine, because your regulator will limit CO2 pressure from the tank to keep the keg at the set PSI, regardless of how much CO2 is already in the beer.

However, you'll need to let your keg sit at room temp for 2-3 weeks to allow priming to occur before chilling it down for serving, or you'll have some residual sweetness from the unfermented sugar.

 

[boomslang]

I'm no expert in kegging, but I've done a few kegged brews a long while back.

From my experience, I've primed the keg, then left it for a week or two at room temp. The secondary fermentation will pressurize it enough to allow you to pour beer from it. As you drink it and it gets emptier, the pressure will decrease. It'll get almost half full and it'll begin to trickle out of the spout. THAT'S when I've added the CO2 capsule. Then you should have a good flow as you did at the start. You may have to add another before the keg empties, depending on how big it is.

Make sure you don't let it get to the point where the beer barely comes out at all; it'll start sucking air back in and you run the risk of an infected batch. You can't over pressurize these home brew kegs either, they'll have a release valve on the top that'll let CO2 back out if there's too much in there.