Hi @Pilleman22,
It’s likely your problem is where you are putting your rotational force.
You probably have it inside the Particle Update, right? Any module inside of the Particle Update will add onto itself every tick. So that’s why your seeing your rotation increase over time- the force is constantly being reapplied.
If you move your rotation to Particle Spawn, it should only apply that force once and keep a consistent velocity.
Best of luck!