I've taken this twice now. I should note that these have been my only hallucinogenic experiences. Previous drug experiences have been with weed (almost daily), MDMA (maybe 10 times in the last 2 years), and cocaine (only once or twice). I must be extremely sensitive to BK-2C-B, based on other people's reports and dosages. Also, I'm a small guy (only 5'4" 120 lbs), so that probably affects things.
The first time I took 125mg with my bf about 3 hours after a light lunch, about 5:30pm. 2 hours later I was feeling nothing. We were sitting on the front porch having beers, and he's suddenly giggly and says that the tree across the street wants to come over and hug him. I get jealous and take another 60mgs, hoping to push myself over the threshold. This may have been a mistake. A half hour later, I go to the bathroom to pee. I look in the mirror over the sink and then turn to look in the mirror in the medicine cabinet. Something looks subtly different about my face in each mirror. This triggers a wave of tingles from head to toe. A couple of other friends show up and I offer them some BK-2C-B too, as the tingles are feeling amazing and I want to share the experience. I split what I have left for them, about 95mgs each. Shortly after this I get extremely nauseous and have to puke. It's oddly cathartic, not unpleasant. I see snake eyes looking up at me from the toilet bowl. This is the beginning of the visuals. Slowly, pulsing waves of colors wash over the walls and ceiling. My two friends didn't experience much, mostly stimulation and some psychedelic thought patterns, slight visual breathing. My bf and I lay on the living room floor and melt into the music that one of my two friends is playing, The World of Synthipop on vinyl. The music takes on an evil tone, but not in a scary way. I have to agree with Psychonautical that this substance is somewhat "dark." We have some antique African masks in the living room that looked very alive. In the bathroom with the light off, a tiny gargoyle peers up at me from the sink. There was also quite a lot of body load for me. My muscles were very tense and getting up to walk to the bathroom was difficult. It was like all my muscles were buzzing. At 3AM none of us is remotely close to coming down, but we all feel like we need to get to bed. My two friends take to the spare room and my bf and I head for the bedroom. I take 1mg etizolaam to facilitate sleep. As I close my eyes, I see pulsating patterning triangles that eventually morph into all sorts of amazing things. Most notably, poodles floating around gold stripper poles with a fluorescent pink background. I was able to fall asleep without too much trouble. I woke up around 6:30am briefly and was still tripping quite hard. Our knotty wood ceiling was alive with the faces of 50 or so people. I immediately decide I need to get back to sleep and close my eyes. Wasn't expecting to still be tripping so hard! I wake up for good around 10 and the visuals are gone, but my brain is fried. I had to go to brunch at noon to meet friends and had a lot of trouble eating. After a few drinks and a few hours, I was back to normal by 4 or 5.
The second time was while camping last weekend. This time I only took 120mg, yet I still tripped just as hard! My tent was like my own personal space ship. While peeing on a tree, several faces formed in the dark and looked up at me. Lights in the distance through the trees became baboons lurking in the woods. Oddly, nothing ever seemed frightening to me, just fascinating. Effects this time lasted around 14 hours.
Next time, I plan to try an even lower dose of around 80mg. I'd like to see if there is a dosage that is "partyable" for me. A dose that offers the euphoria/stimulatuon and some minor visuals without such a strong trip.