DISCLAIMER: Injecting pills is bad enough, injecting 12 fucking 5mg pills is much worse. But if you choose, here is a basic set of instructions, based on how I do it. ALso, I assume you have clean needles, and clean supplies, etc. ALso, mine we're a different generic then yours. They we're very smal, I am gonna assume yours are small as well and don't gel up:
First off, oxycodone has a solubility in water of 40mg/ml(thanks to muvolution for pointing this out.) BUT, the fillers are going to reduce this. Basically, you'll be lucky to get 30mg, considering the binder. But nonetheless, I'll suggest 6 pills at a time. You will need to do 2 injections back to back for this.
1. Get a shot glass, or something similar. DO NOT use a spoon. Now, crush up all 12 pills.
2. Put about 2.25ml of water in, to compensate for the fillers. Now stir it up good, and wait.
3.Let it sit for a few minutes, stirring occasionally. Eventually, all(or most) of the oxy should be dissolved.
4.Now, if you have a micron filter, use it. But you probably don't, in which case, get some cotton, such as q-tips or cotton balls, etc. AVOID USING CIGARETTE FILTERS! Now draw up half the solution in one syringe, half in the other. As soon as you do, make sure to taste it. I have noticed the taste gets more characteristically bitter as the oxy dissolves.
5. Now you have the choice of running it through again, to get any more oxy out. But I wouldn't bother. Instead, put it another shot glass, and filter a second time. This is a piss poor substitute for a micron filter, but it works.
6. Now, inject each shot back to back. AFterwards, you can add more water to the filler in the shot glass, to see if you can get more.
Note that this is the quicker way; a more efficent way would be to only do a few pills at a time, and then run the same water through a few more pills, to get as much oxy out of the batch. Really, if you know the basic principles, there are all sorts of ways to experiment. But ultimately, it is NOT going to be very effective doing this; if you had a 3ml syringe, MAYBE, but with a 1ml, you are honestly just better off eating them, as you are just going to be doing multiple weak shots, and investing a lot of time.
Again, there is possibly a better way of "trying" to extract oxy, but this is as good as your gonna do in a pinch. Remember, only 6 pills a shot, and honestly, 4 or 5 is ideal, as you will inevitably lose some in the binders.