Shields?

[TosaInu]

I only hear the bell: but there even were Russian sappers (?) in WW2 wearing something like a steel cuirasses. I don't know whether it was supposed to make them bulletproof, but it probably did give them some protection.

Tokugawa Ieyasu (16th and 17th centrury Japanese warlord) was saved more than once from bullets thanks to his armour.

Bulletproof cuirasses are made, they were tested by firing balls on it.

A modern test.

1. 24 mm wooden board (yes, there's wood and wood).
2. 48 mm wooden board.
3. 1 mm iron plate (yes, there's iron and iron).
4. 2 mm iron plate.

9mm caliber black powder arquebus (grains of charge not listed).

30 meters, four targets, four shots: each was pierced cleanly.
50 meters 1 and 3 pierced cleanly, 48 mm board entered for three-quarters and bullet entered the 2 mm iron plate, but did not pierce it.
   Turnbull The Samurai Sourcebook.