IMHO, if you choose to carry OWB, then a retention holster is the ONLY way to carry your snubby. I'd recommend at least a Level II such as a Blackhawk Serpa. Adding Crimson Trace laser stocks will give you an additional leg-up with this excellent choice of a CCW.
Practice ammo should be the same as your carry ammo. You don't want any surprises when you need it most. With a snubby, even though you can make accurate 50 yard shots with it, 90% of all gunfights are within 9 feet, so +P is really of no consequence. I look for penetration rather than a (possible) larger wound channel. Either ball ammo or maybe the new gel-filled HP's (I have yet to research anything about them).
Practice you reloading with your preferred device for carrying extra ammo. Get at least 10 or 15 dummy rounds and "dry-fire" and reload.
Congratulations! Welcome to the Snub-Club.
