Just because something worked for one thing, doesn't mean it'll work for something else, K'd-OUT is bang right, the doc will start to look for alternatives like fucking patches, and other shit stuff that isn't addictive but in turn most often, isn't effective.
You're on Bluelight, which would suggest that there is an element of recreational(ism) in your motives, not accusing, just throwing it out there...
There is a sure fire way to enjoy them, and properly take the pain away, but that's heading down a very bad path, specially with the amount you have, so I ain't suggesting it but when I was legitimatly hurting, they took me off a morphine drip, and put me on oxycontin because "gram for gram oxycodone is stronger than morphine" I was well chuffed, so I got home, snorted 80mgs, and....nothing. Morph and Oxy use the same receptors, your tolerance for oxy will already be affected by the daily morphine.
If you are really hurting tell em, they can take the dose well up past 100mgs, and by the time you get that far up the dose ladder, you aint gonna be getting anything else, and even if you did, it wouldn't help/be fun/help...
Talk to your pain doc man, they know their shit, pain can be managed, and you might of drawn the short straw in the physician you have been given, but oxy might just be out of reach mate..
You tried a weed?