Hand guns and steel - chain mail - leather?

I was wondering how hard would i need steel to be FLEXIBLE to Create armor as in med evil types of armor yet strong enough to withstand shots from most common hand guns at close blank range to mid-far range hand guns and un fragile to withstand clubbing hits from bats to prevent cracking. My goal is to make an mid evil plate-chain mail to void most common criminal weapons that a criminal can get there hands on. as well if you know about leather that's FLEXIBLE and harden to with stand stave and piercing attacks that will be under the chain mail.