Placing an exploding Car or Barrel
Under KActor/KActorExplodable you’ll find CarExplodable and BarrelExplodable.
Alternatively, you can use the quick selection menu at the top of POSTed and go to Props > Exploding car / Exploding Barrel and it will place one at the location of your camera.
Place the car or barrel as you would any other static mesh. When it is in position, open up it’s properties.
The present default meshes for the car and barrel are a car and a barrel static mesh respectively and you can change these defaults if you would like to use your own models. When you do this you will also need to make sure you assign its broken mesh to match it. The broken mesh is designated under the KActorExplodable properties. If there isn’t a broken version of the mesh available, use the same mesh for the broken version.
Beside the mesh, the only real tweaking required is the collision on these props. For cars use the default staticmesh collision. Barrels will work perfectly with the cylinder collision though and should be changed to that, as it will help optimize performance a little. You can change the radius while there too.
Once you’ve got it functioning in game you may want to tweak the KActorExplodable/ExplosionMagnitude. The default setting for a car is 80,000 and 40,000 for a barrel. Likewise the health may need tweaking for large vehicles.
Other variables you may want to tweak:
When set to true it will limit what damage the object will take to the type of damage specified under "Damage Filter"
When set to true, the object will explode only if triggered.
The texture that will be applied to the broken static mesh version of the model after it is blown up. Use this if you want a skin other than the default.
These variables apply force in the specified direction (relative to the X, Y and Z in the editor) to control explodables in situations where you won't want it to block a doorway or something else.