Your answer varies depending & varying upon opiate tolerance.
I'll base my reply in regards to your post about OC 20's, its effect & your frequency.
A Dilaudid, which is Hydromorphone, is a very strong pain reliever; it's 8-10 times stronger than Morphine and 5-7 times stronger than Oxycodone in comparison to its strength & potency. A 4mg Dilaudid when taken orally is equivalent to 20mg of Oxycodone. I have read that its strength of effect & euphoria is greater when snorted, and of course greatest when injected via IV. Because Dilaudid is so potent & strong, it is only available up to 8mg in doses of pills for its strength & potency and thus potential risk of abuse & easy overdose.
Since you have a tolerance that is moderately low, I would recommend snorting Hydromorphone for the best effect in your situation, and since you're used to getting high from 20mg of Oxycontin, you should be able to feel the same sensation from 4-6mg of Hydromorphone. I think that 8mg would be best for you because Hydromorphone in its oral form isn't as strong as it should be due to your body's digestive chemicals. Due to its decrease in potency & strength in oral form, you probably won't like Hydromorphone as much as Oxycodone/Oxycontin because it's not as effective in the body whereas Oxycodone/Oxycontin is very effective both orally and intranasally because of your body "accepts" & "doesn't break-down" the chemicals as much making the % of the Oxycodone/Oxycontin that you take more effective/felt. Hydromorphone is still stronger than Oxycodone but please try to understand that in oral form and depending on tolerance Hydromorphone may not seem as effective & "good" as Oxycodone; so understand that of the 20mg of Oxycodone/Oxycontin is absorbed/in effect 60%-80% of its mg orally & 50%-70% intranasally, and while Hydromorphone is more potent & stronger, the body absorbs/takes effect only 30%-35% orally and about 50% intranasally. Any opiate in effect via IV is always absorbed & taken to effect 100% of its strength & potency of its mg, and its strength & potency as well as effect always obviously varies on the variation of opiate medication/variation & chemical make-up.
Thus when you have a tolerance and such, you really can't go by an opiate medication's strength, of which & because the strength & potency is typically based upon IV - IV is the most direct method for an opiate to take effect 100%. So when you are used to taking a specific opiate medication, such as Oxycodone/Oxycontin, as well as build a tolerance that makes it effective, you need to base any new opiate medication's milligram dosage on the bioavailability of your ingestion method and also its strength & potency. Mostly if not all opiate medications are compared to Morphine to determine strength & potency, so you need to consider both opiate medications' strength in comparison to Morphine as well as know your tolerance - the milligram dosage that effects you - and put the bioavailability for your preferred ingestion method of each opiate medication into a calculation.
Dose of Oxycodone/Oxycontin that effects you: 20mg
You preferred method of ingestion: Intranasal (snorting)
Calculation Theory: The median bioavailability statistic of effect for Oxycodone/Oxycontin is about 63% (really 63.5%). The effect that you want takes you 20mg of Oxycodone/Oxycontin while your body is really absorbing about 12.7mg of that opiate medication to give your desired effect/reaction/feeling.[/b]
New opiate medication you're trying: Hydromorphone
Your preferred method of ingestion: Intranasal (snorting)
Calculation Theory: Since you prefer snorting, the opiate medication Hydromorphone statistically 50% effective. The oral (pill) potency & strength of Hydromorphone is greatly reduced and varies via milligram dosage; oral Hydromorphone is digested by the body similarly to Morphine and thus drastically broken down but its strength & potency of its general chemical make-up allows the remaining proportion to be absorbed by the body and very effective. Effectiveness, of course, also depends upon tolerance and factors listed above.
Oral Hydromorphone (pill) vs. Oxycodone - My Personal Theory
Oxycodone is 1.5 times stronger & more potent than an equal dose of IV Morphine., though it has been studied to be equally strong & potent
here via IV. Oxycodone was created to be this effective as an oral opiate medication though, while Hydromorphone was created 8-10 times more potent & effective than IV Morphine as an IV opiate medication whereas its oral form is new & not as strong.
Hydromorphone's bioavailability orally and intranasally decrease its strength & potency to about 50% if you have built a tolerance to opiate medications, such as Oxycodone. Thus while Oxycodone is 1.5 times stronger than Morphine, oral Hydromorphone is about 4-5 times stronger than Morphine. Since snorting Hydromorphone has 50% absorption & effect, and it's orally about 4-5 times stronger than Morphine and thus about 3 times stronger than Oxycodone generally...let's calculate.
It will take about 8mg to 10mg of to digest an effect 20mg of Oxycodone/Oxycontin for you.
8 divided by 2 is 4...times 4-5 is about 20mg...but you only want to feel about 12mg which gets you high.
4-6mg of Hydromorphone via intranasal should give you the same feeling as Oxycontin 20mg based on your usage and tolerance.
Hope that helps.