|Spoiler Alert: This page contains spoilers. Read at your own risk.|
Heavy Metal Burst wasn't developed as a Strategic-Class Magic from the beginning, but was developed as a tactical-class magic, originally known as "Metal Burst" before.  After producing results that exceeded expectations, it was reclassified and renamed.
Heavy metals are transformed into high energy plasma; the magic disseminates amplified solar ions over a wide area by creating gas, an electromagnetic repulsive force, and increased high pressure. 
The speed of the beam from the Brionac is about a hundred times the speed of sound. 
Heavy Metal Burst can't produce enough power unless there is enough heavy metal that exists in a certain mass, and the effect is limited under geographical conditions where undulation is severe. Although, Heavy Metal Burst has a greater degree of freedom than Leviathan, which can't demonstrate its true value unless its used on terrain with plentiful water such as an ocean, wide lake, or a big river. Though in terms of being influenced by geographical conditions, it is inferior to Ozone Circle and Agni-Downburst, but when conditions such as power and activation speed is introduced, Heavy Metal Burst is the equivalent of a Strategic Ballistic Missile. 
Brionac is a magic weapon that utilizes the Free After Execution (FAE) Theory.  It's a portable weapon manufactured for Angelina Kudou Shields, with it's power being equivalent to that of a battleship; possessing a range and output that can be freely controlled. 
Dr. Abigail Stuart of the Shawmut Research Institute, developed Brionac. 
Brionac is a thick pole eighty centimeters in length. About two thirds of it is the same width as the handle of a tennis racket, and the remaining one third is a cylinder with a larger circumference; at the border between the two.