--- a/net/minecraft/server/ReloadableServerRegistries.java
+++ b/net/minecraft/server/ReloadableServerRegistries.java
@@ -60,6 +60,7 @@
         return CompletableFuture.supplyAsync(
             () -> {
                 WritableRegistry<T> writableRegistry = new MappedRegistry<>(type.registryKey(), Lifecycle.experimental());
+                io.papermc.paper.registry.PaperRegistryAccess.instance().registerReloadableRegistry(type.registryKey(), writableRegistry); // Paper - register reloadable registry
                 Map<ResourceLocation, JsonElement> map = new HashMap<>();
                 SimpleJsonResourceReloadListener.scanDirectory(resourceManager, type.directory(), GSON, map);
                 map.forEach(
