detect a hit with bullet

Questions & Answers
1

I can shoot bullets from a gameobject on FPS but how do I detect a hot with an object?
I shoot an object called “Wall” with a bullet but no hi gets detected?

	  Rigidbody mybullet; 
	  mybullet = Instantiate(projectile, transform.position, transform.rotation) as Rigidbody;
      mybullet.AddForce(transform.forward * 1000);
	  Destroy(mybullet.gameObject,3);
		_bullets2.Add(mybullet);

…

void OnCollisionEnter(Collision collision) {

	if (collision.gameObject.name=="Wall")
	{
		Debug.Log("Hit wall2");
	}

}

2

It could be a number of things but my first guess is that it’s probably that the bullet is moving too fast for the collision to be detected; check the Collision Detection settings on the bullet’s inspector and see if changing it to Continuous helps.

See this thread for some similar solutions Issues with Continuous Dynamic collision. - Questions & Answers - Unity Discussions

Other possible problems could be that you’re using the wrong method for the type of colliders that you are using (trigger or not), or that the collisions between the two layers of the objects themselves might be disabled inside the Physics Settings.

By the way, if you don’t plan on displaying the bullets you could pull this off with just a Raycast (unless you want to include travel time and don’t want the bullet to hit immediately) – that way you A) won’t have to worry about rendering the bullet, B) bullets won’t use up physics time and C) you won’t have to instantiate a game object (which costs CPU time.)