Ue 5.5 physics handle replication issue

Development Programming & Scripting Multiplayer & Networking
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1

Hello Everyone,

I am having an issue with creating a grab and hold / drop system over multiplayer. However I have not been able to lift this project off the ground because already I seem to be having an issue with it. I have looked literally everywhere on the net for some sort of guide or explanation to the issue but I am unable to find something relevant to this issue.

I am using UE 5.5 and I am trying to replicate the physics handle correctly over the network. However, while the server can pick up and move the object find and the movement of the object is correctly replicated, when I try it from the client side there seems to be this weird issue that unless the object is 2x in size/scale the client cannot interact with it, so then I scale it up, when I do this, the client can then interact with it however the object wont lift off the ground even when pointing the camera up and will only allow sliding it across the floor. This movement is replicated to the server and other clients.

What exactly am I doing wrong here?
I have uploaded a video to youtube to demonstrate the issue. Addidionally here are some screenshots.

Any help regarding this issue would literally be massively appreciated as I have exhausted all other RSS, google, forums, youtube, AI - and yet I find nothing. No tutorials or guides.

Blueprint1
Blueprint11681×764 211 KB

Blueprint2
Blueprint21678×844 184 KB

Blueprint3
Blueprint31687×847 180 KB

ReplicateOnobject1
ReplicateOnobject11629×670 212 KB

ReplicateOnobject2
ReplicateOnobject21918×834 311 KB

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classic authority bug, and the 2x scale clue confirms it. your handle runs on the machine that clicked, so on the server it works (server owns the object), on the client the handle drags a sim the server keeps correcting back. a bigger object just has more mass so the correction is less visible, its not actually working there either.

fix: the grab must live on the server. client sends a Server RPC with target plus grab location, server creates and drives the physics handle, the transform replicates back like any server sim. never drive the handle on the client directly. release the same way, client requests, server releases and applies velocity. also scale LinearStiffness and LinearDamping with the grabbed mass, small props need much lower stiffness or they oscillate, and keep Replicate Movement on for the grabbed actor.

grabbing in multiplayer is built step by step here: Networked Physics - Gameplay Tutorial
mindset first if resim is new: Networked Physics - Fundamentals