built up tolerance to morphine

[mick mouse]

SWIM is currently taking 30 mg. MSIR every 6 hours as needed per docters orders for chronic pain and has been doing so for about 3 weeks. Prior to that SWIM was on 30 mg MS Contin twice daily. SWIM has recently noticed that, when accidentally taken in a recreational setting and at doses ranging from 3-5 times recommended dosage, the effects seem to be muted at best. SWIM understands that tolerance can build up over time, but going from 30 mg. to 150 mg. in a week or two and not feeling the effects seems to be rather odd.
Recently SWIM was at the above mentioned rec setting, took 150 mg., drank 1 quart of beer, and .... nothing! No euphoria, sedation, inability to function, just nothing! SWIM has tried 60 mg. IV and 90-120 mg. rectally with basically the same result. SWIM HAS tried 90 mg. orally followed by 2X 30 mg. IV about 20 minutes apart and damn near tripped, but has been unable to duplicate the experience, regardless of the method/combonation used. What is a "normal" recreational dosage of morphene, assuming one was male, 200 pounds, used morphene less than 2-3 months, and is not habituated?