When shooting my electrical conduit, concrete filled projectiles, I had formerly painted them a bright, blaze orange and thought that this color would make them real easy to retrieve.  Wrong, for my particular location, the ones I painted white were a "piece of cake" to find.  From now on, it's going to be only the white color for the projectiles that I WANT to retrieve. 
And here is another bowling ball mortar from the Casper Shoot:

Blaster (Bob in So. CO)