"I recently tried using a pressure cooker to do an oil extraction. I added about 10 grams ab ground cannabis buds to a cup of coconut oil and placed inside the pressure cooker and then cooked it for 30 minutes. I did not tightly seal the jar in order to prevent the lass from cracking due to temperature differences inside and outside the jar. The temperature is supposed to be about 240-250 degree Fahrenheit. The oil did not seem to be very potent, but I am not sure of the THC/CBD of the cannabis, which was homegrown. I am guessing about 10%. Do you see any problem with this procedure? The advantage of this is that one can control the temperature and time and not have to monitor with a thermometer."