If they are ABG then use ice cold water. You prolly can't do more than one MAYBE two pills at at ime htough. the 15mg's are the WORST to IV if you have ANY tolerance to opiates cause theres sooooooo little drug in them.
if you get the M (or pretty much any other brand) do the boil drop method. this is how i do it- i cut a quarter inch off a cigarette filter, have it on standby, i get the coating off pill/crush it in a cellaphane, leave the powder in the cellaphane off to the side. throw 120-140 units of water in a metal spoon, heat the spoon w/ lighter until water boils. once the water has reached a deccent boil, quickly put the spoon down, pour the powder from cellaphane in, give it a cpl quick stirs, throw cotton (which is pretty big) in there, and suck it up. i try to have everything ready and within arms reach so it gets done before the liquid cools back off.
also, before you shoot it, id advise sticking the syringe loaded with morph in front of a fan, IVing water that was boiling moments before prolly isnt good, ive done it a few times and most of the time it didnt seem to matter but one time it did feel like i was burning the inside of my arm i could feel the heat in my veins, prolly not good.