Uploaded October 2018 | Updated September 2026, 2 weeks ago

---

There is a long standing misconception about blowing up blocks while being moved by pistons. The blast resistance of moving blocks may be zero, but they still dampen the blast power. So, by removing the blocks surrounding the explosion, the explosion retains more power for the outer blocks, exploding up to about 20% more. Moving blocks are NOT treated like air.
They are treated more like zero blast resistance blocks, which still have an attenuation. minecraft.gamepedia.com/Explosion . This may seem like a small difference, but when designing a blast chamber, it's very important to know how the explosion works.

The inspiration for all this was Maizuma Games, since he recently published this video on his "implosion chamber" youtube.com/watch?v=SATsBG4a-Ug which inspired me to make this vertical blast chamber in the first place.. He and I also discussed this in some comments, which led me to do more research, wherein I discovered the peculiarity on blowing up moving blocks. He commented he is getting 288 per TNT, but I'm getting up to 380 blocks per TNT (unreliably). Of course, my system is designed for a cobble farm while his is designed for a tree farm, so it's not quite fair to compare them.

The piston arrays are my biggest obstacle. Quasi-connectivity makes it real tough to push down just what you want.

World dl (1.13.1). This has a lot of other testing. /tp -5 ~ -60 to get to the content of the video. It's 100 megabytes because I couldn't get MCEdit to work on 1.13. There is a lot of other stuff in the world.
mega.nz/#!g8R0jAIC!_nLioI4tjwOFnu4xeYP8Kam9_M18BzEmfce3gtOgvA8