Honestly, if you are going about skin popping your drugs the right way, which after my how-to should have you ace in a day's worth of shooting anyway, you really shouldn't ever risk doing an IM shot with something as unregulated and dirty as street dope. If something bigger than just the needle head gets into those muscles everything around the site of injection will start to necrotise and sometimes half the muscle is lost in the pursuit of way to get high quickly, even though there usually is another way, as I alluded to in the skin popping guide. The only preparations that you can ever really know are safe to IM are ampoule preparations that either come from a hospital, stolen from a stock room, or are diverted from people with horrific pain in a situation where they are supplied opioid ampoules while they are bedridden from an illness; and those cases are very rare that you will ever see a sustainable supply of ampoule preparations of IV opioids. In fact, I think that me even bringing up the possibility of a well supplied junky with ampoule preparations of strong opioids is pretty damn unbelievable except in the cases where some European studies will supply heroin or other IV preparations of opioids to only the most unsavable needle junkies, and even then I am sure that they have ungodly restrictions about how much you can inject at a time, where you must inject, and how often.
I will say confidently that I have never in my medical career even handled more than 1 order for a high potency concentration of opioids ordered to specifically be administered in an ampoule along with syringes, and that case was more or less to supply a patient with horrifically painful disease who knew her only fate was death sooner or later a way to basically have the doctor wink harder than anyone ever has and for the patient to basically have herself be comfortably put to rest in her own time on her own terms. The doctor who did this immediately regretted it on a legal basis, even though he never really gave it for assisted suicide he was scared for over a year that the police would come knocking on his door any day to indict him for manslaughter or some exaggerated charge related to a patient's right to die.