I mean you can fiddle with the collision more. It may work better if the ball has a box collision and isn't rotated at all. You can use the "set angle of motion" to let you shoot where you aim.
If the bullet behavior's bounce still isn't acceptable you can use the physics behavior instead to move the ball. Give the tilemap and the ball the physics behavior, make the tilemap immovable, and when you launch the ball you'd set it's velocity with:
set velocity to (speed*cos(angle), speed*sin(angle))
You may need to fiddle with some of the ball's physics properties to tune it. Stuff like collision shape and elasticity. You may need to disable collisions between balls or change the gravity with events.
If that still isn't satisfactory you can calculate the surface normal of a collision and do the bounce with math. Here it bounces a perfect ball with a tilemap. This gives more control but isn't as simple to drop in.
https://www.dropbox.com/s/r7ptcicrw0k753w/bounce_sdf.capx?dl=1
wow this is the most stable bounce behavior i've ever found in construction, and you made a physics manual, looks good, thanks R0J0hound i'll learn this more