That will work just fine, the CO2 will fill the headspace and hold the pressure that you set on the regulator. I would recommend purging with CO2 a few times after filling it up.
End of the Line Brewing
Primary: Caramel Cider
Secondary: Bourbon Vanilla Porter
On tap: Some Sort of IPA, Cherry Cider
Bottled: Belgian Sour (1st place winner Binny's Chicago Comp)