Hey TwystedXYZ,
Last time I checked, anything above sqrt(500)
doesn't work at all due to a check in the vanilla Minecraft server code that completely blocks the packet if the distance is higher. I left a comment on that code linking to where that check is in the Minecraft source code. I've also explained in a bit more detail in this WurstForum post.
So unless something has changed an that check doesn't exist anymore, I don't think adding an extra zero there would be a good idea as it would just prevent MaceDMG from working.