Ballistic shields are a thing really. Though the portable onea only do small calibre. To have something interesting against explosions you need to go sci-fi or

Ballistic shields are a thing really. Though the portable onea only do small calibre. To have something interesting against explosions you need to go sci-fi or have some magic that can dampen them. We had a lot of sport having fire and alchemical powder be extremely overpowered in e.g. D&D. Villain lair lacks an entrance? Blow up a hole. This castle has walls? Dig and mine it. Enemy has an army? Now they don't, it exploded...