I witnessed the full power of an M777 howitzer, and the piercing 'boom' of the artillery cannon shook me to my core

• Business Insider recently traveled to Fort Sill, Oklahoma and saw US Army soldiers training on artillery.
• Our reporter witnessed soldiers firing the M777, a powerful howitzer that's been used in Ukraine, among other wars.
• The artillery piece made a very loud 'boom' when it fired, shaking the ground around it.

A 155mm shell is loaded into the massive, almost 10,000-pound gun. A few seconds later, a US Army soldier yells out. "Fire!"