i have to ask why you'd snort oxymorphone IR when you bang dillies? oxymorphone is like 50% stronger than hydromorphone when IV'd, and lasts longer too. I have snorted the pre TRF oxymorphone, and the first time 10mg was a little too much. I had 5 30s that kept me effed up for the better part of a week. If I had an IR I'd be finding a rig, but that's me. iirc, oxym has a bioavailabilty of ~ 40% when snorted. use the search engine here, im sure this has been covered before by persons more knowledgeable than myself.
eta: injecting hydromorphone hits you in about 5-10 seconds, no drug snorted is gonna have that rapid an onset, even oxymorphone