The 1.21.41 update introduced a universal 16 block/tick movement limit for all entities to prevent crashes. While effective for most entities, this unnecessarily restricts TNT which doesn't cause stability issues at high speeds. Unlike Java Edition where no such cap exists, this artificial restriction severely impacts TNT cannons，Flying machines and all redstone contraptions relying on high-speed entity movement. Our testing shows this artificial cap breaks many TNT-based contraptions that rely on uncapped movement physics.
Steps to Reproduce:
Load provided test world "Test map(5)"
Activate "Start testing" lever. The test map contains a command-block based "motion tracker" that records entity movement every gametick (similar to a real-world ticker tape timer). This system works by command blocks executing every gametick and detecting entity positions.
Observe marker blocks placed for entities every gametick:
TNT: TNT blocks
Zombie: Soul Sand
Villager: Emerald Blocks
Chicken: Iron Blocks
Pillager: Fence Gates
Breeze: Gold Blocks
Observed Result:
All entities show exactly 16-block spacing between markers, proving the hardcoded limit. This differs from the Pre-1.21.40 behavior (single endpoint marker) and Java Edition.
Expected Result:
TNT and other entities should move without artificial limits (like Java Edition).
Attachments
Comments 8
Can confirm. Here is a conversion rate table related to entity distance caps over multiple time periods:
Max entity movement distance in 1 game tick | Max entity movement distance in 1 real world second | Max entity movement distance in 1 real world minute | Max entity movement distance in 1 Minecraft day | Max entity movement distance in 1 real-world hour |
|---|---|---|---|---|
16 blocks | 320 blocks | 19200 blocks | 384000 blocks | 1152000 blocks |
Thank you for your report!
However, this issue has been temporarily closed as Awaiting Response
Could you please provide more details, what is the attached world supposed to demonstrate, and how should it be interpreted?
Could you also provide us with a video showing and describing the issue?
This ticket will automatically reopen when you reply.
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This was stated as an intentional change in the 1.21.40 changelog:
However, it creates a disparity, because this limitation does not exist in Java Edition and it breaks a whole category of contraptions that players use in Java Edition. It seems like more a hack fix than a proper fix to the crash issue.
The cap may not apply to projectiles by design, because projectiles get ticked outside of simulation distance (see (MCPE-178258; this is a factor in (MCPE-167769) (MCPE-184195)). Or the projectile component may just happen to use different functions than the movement component. 🤷♂️