Ultrasonic transducer beam models are developed to predict the average received pressure reflecting from the front surface of finite-sized shapes with simple curvatures. A general surface integral model is derived that combines the Rayleigh-Sommerfeld integral with the method of stationary phase and the Kirchhoff approximation. Numerical evaluation of the 2-D surface integral is simplified by employing the edge element technique and ray tracing that obeys Snell's Law. Algorithms are developed that determine the Snell's Law ray path for a ray reflected from spherically curved interface between any given point source and field point. On-axis scans of the average pressure received at the transducer of the front surface reflections from spheres of various sizes are calculated and compared with scans of planar interfaces and point scatterers.