Neither.
Short action.
The 223 is considered a Short Action rifle.
Short action
The bolt action rifle was invented around the late 18th century and wasnt till ww1 1914 it was widely used and so it wasnt long after this actual bolt action hunting rifles were made so in short early 19th century. However single shot rifles were used long before this.
Try Brownell's
Yes
.223 is considered a short action cartridge.
It depends on the particular model of the rifle, not the caliber it is in. What model and make is it?
For open carry and hunting, federal law alows you to have any type of rifle which is not a machine gun or a short barrelled rifle. That means any caliber up through .50 cal in any action type including break action, bolt action, pump action, lever action, or semi-auto. Full-auto (machine guns) are highly restricted.
If the rifle is chambered for the .308 Winchester cartridge, then long or short action can safely fire it. Long or short refers to how far the bolt travels when opened. The .308 is typically a short action- the 30-06 and longer cartridges cannot cycle thru a short action, and must be used in a long action rifle.
Normally a rifle chambered for .243 Winchester would be built on a short action.
The .17 Remington cartridge would be chambered for a short action rifle.