I don't think I'll be touching nitrous outside of a rave or the odd tripping get together if somebody in the group brings some. In march I bought 600 cartridges from a website, and a whipped cream dispenser. Having that much around and ready access to it leads to some problems...but I'll get to that later.
This is the dispenser I had, for reference:
You have to actually take the top off and screw the other piece on with the cartridge inside it, which is more of a hassle than some of the other ones I've seen, but it works pretty well in my experience.
I read that you can fit about 3 cartridges into this particular dispenser, but I never actually tried that, just stuck with 1.
Anyway, how i would do this, is I would pre-load 1 cartridge into the dispenser, then put another into the loading cap (the thing you screw on to put the nitrous into the dispenser), and have the rest of the cartridges i planned on using in a row next to me, all oriented so I could easily pick them up and put them into the loading cap even when I was fucked up. Apparently I was born with amazing lungs because I can inhale the entire cartridge worth in one breath (none of my other friends seem to be able to do this?).
So basically, I would inhale the entire 1st cartridge, hold my breath, take the top off, screw the cap on (to put another cartridge in the dispenser), unscrew it, put another cartridge into the cap and set it down, then put the top on it, exhale (yes i can hold my breath that long, i got very good at doing that process so it would only take me about 15-20 seconds...practice for the win), and then inhale the entire second cartridge, and repeat this until i had gone through the entire pre-chosen amount of cartridges i had set out for myself. I started wiht only 2 (so I only had to do the process i described up there once), but near the bottom of the 600 cartridges I bought (which I surprisingly was able to make last a couple weeks), I would be doing 5, 6, 7, and even 8 and in 2 cases, 10! cartridges in a row with no oxygen breaths in between. I'm sure this is horribly unhealthy for myself, but I found that doing that method, I could make my "trip" (is it really a trip?) last for 5 minutes or even more.
The cartridges I had have 6% oxygen in them, I don't think what I did would be possible with medical grade do to the amount of time i was going without oxygen breaks. At some point, very close to the bottom of my stuff (like in the last 150 I would say), I did 15!!!! in a row using my method (that is, no oxygen break), and I passed out shortly after inhaling the 15th one. I had amazing thoughts/visions in the 15 minutes or so I was passed out for.
And then the point when I realized I would probably never buy this much again, because I apparently do not have the self control necessary to have that much around, I did literally 29 (I know its exactly 29 because it was my last 29) using my method, with no oxygen break. I blacked out (not passed out, but total black out even though i was conscious, no memory of this time) after the 5th one, but apparently, due to I assume my practice with this method, I was able to keep reloading it without breathing oxygen, and did another 24! I don't remember anything after the 5th one (literally nothing), but I woke up on the ground, freezer burn on my hands because apparently after loading 29 in quick succession, even the dispensers get ice cold), unaware of who I was, or what my name was...completely dissociated. I felt like I was everything...not a person or individual conscious, just everything. I couldn't see or hear any real things, just saw pure rainbow and light (no details), and I could only hear the waaaaaaaahwaaaaaaaaahwaaaaaaah sound I'm sure you guys are familiar with...the interesting thing though, was that i was in this disociated state for over 10 minutes. I don't know how it could possibly have lasted that long, and I would just chock it up to time dilation, except my friends helped me up off the ground as soon as i woke up from being passed out (when I felt the freezer burn and started seeing the rainbows), and they told me I didnt speak or respond to anything for 10 minutes (which they could accurately judge since they were sober).
Those 10 minutes were so beautiful and I literally cannot describe how I felt...I felt like everything, all at once. It was fucking amazing.
But despite that amazing experience, I could have gotten serious damage from that, and I don't think I will ever buy a large amount of cartridges ever again, for fear I might do something like that, and not have friends there to help me.
Anyway that's my experience with nitrous...I'm VERY glad I had that last "trip", because it was the most beautiful thing that I've ever experienced, but I'm pretty much done with nitrous.
For people who say nitrous can't be psychedelic...it can, and was, for me.