https://psychonautwiki.org/wiki/4-AcO-DMT
In writing this message, I went back to my notes and see that I had taken 20mg, not 25mg, that first time.
I abbreviated my history of experiments in my original message, but I had actually had first tried a different tryptamine in a series of ramped experiments a few weeks apart. It was 4-aco-det, aka ethacetin or ethylacybin. 4mg, then 10mg, then 18mg, then 30mg. I chose that one because my reading indicated it was less intense than 4-aco-dmt. All were underwhelming, with little body load, no open eye visuals, and mild, gossamer closed eyed visuals.
When I switched to 4-aco-dmt I should have ramped as well, but the previous experiments led me to believe that I was a low responder to tryptamines, so I started at 20mg. That is when I learned my lesson to not make assumptions: always ramp with a new substance from a very low dose.
You think? Jeebus! Terrance McKenna would call 10mg of psilocybin a heroic dose. Some of the most intense visuals I have ever seen were on 10mg of psilocybin.
So if close relative means that it requires 2.5x more, then okay, but if they are anywhere near 1:1, then that was a freaking monster dose.