Projectile Velocity Starts at Double

Development World Creation
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1

I have a projectile spawned at zero velocity, which I then set to an actual velocity via blueprints. The projectile seems to start with an initial jump at 2x the velocity I set before normalizing back down to the correct velocity. To test, I am using Set Velocity with a Vector [0, 0, 5000]. The output below shows the Get Linear Velocity of the projectile at every tick with the vector length at the end of the line; the first tick seems to always show the projectile at 2x - for the test below, it starts at [0, 0, 10000] before normalizing closer to [0, 0, 5000] afterwards. In other tests I’ve done with 10000 as the initial velocity, the first tick is at a velocity of 20000. I have gravity disabled to try to make sure nothing else is affecting the speed of the projectile. At lower speeds, this initial kick is not noticable, but at higher velocities, it looks like the projectile spawns at the wrong location.

LogBlueprintUserMessages: [Projectile_C_0] Server: X=0.000 Y=0.000 Z=0.000

LogBlueprintUserMessages: [Projectile_C_0] Server: X=0.000 Y=0.000 Z=10529.637 - 10529.636719

LogBlueprintUserMessages: [Projectile_C_0] Server: X=0.000 Y=0.000 Z=5000.138 - 5000.138184

LogBlueprintUserMessages: [Projectile_C_0] Server: X=0.000 Y=0.000 Z=5008.175 - 5008.174805

LogBlueprintUserMessages: [Projectile_C_0] Server: X=0.000 Y=0.000 Z=5119.270 - 5119.27002

LogBlueprintUserMessages: [Projectile_C_0] Server: X=0.000 Y=0.000 Z=5000.059 - 5000.058594

LogBlueprintUserMessages: [Projectile_C_0] Server: X=0.000 Y=0.000 Z=5000.034 - 5000.033691

LogBlueprintUserMessages: [Projectile_C_0] Server: X=0.000 Y=0.000 Z=5015.441 - 5015.440918

LogBlueprintUserMessages: [Projectile_C_0] Server: X=0.000 Y=0.000 Z=5000.070 - 5000.069824

LogBlueprintUserMessages: [Projectile_C_0] Server: X=0.000 Y=0.000 Z=5035.363 - 5035.362793

LogBlueprintUserMessages: [Projectile_C_0] Server: X=0.000 Y=0.000 Z=5013.565 - 5013.56543

LogBlueprintUserMessages: [Projectile_C_0] Server: X=0.000 Y=0.000 Z=5096.301 - 5096.300781

LogBlueprintUserMessages: [Projectile_C_0] Server: X=0.000 Y=0.000 Z=4999.932 - 4999.931641
2

Does it happen when you spawn the projectile with an initial velocity?
Physics simulated actors can sometimes be rather tricky when not using initial values and setting them at runtime.