Here are some interesting videos where a 50 caliber gun shoots regular and armor piercing rounds and a 20 mm gun shoots against titanium.
An inch and half of titanium does not get penetrated by the armor piercing 50 cal or 20 mm.
Although with 90 degree angle there is deeper penetration.
Brian Wang is a Futurist Thought Leader and a popular Science blogger with 1 million readers per month. His blog Nextbigfuture.com is ranked #1 Science News Blog. It covers many disruptive technology and trends including Space, Robotics, Artificial Intelligence, Medicine, Anti-aging Biotechnology, and Nanotechnology.
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