We might have a more relevant expert cooking up an answer for you, but it turns out someone tested a few reproduction grenades based on examples found in the 1684 wreck of the French vessel La Belle, used by the explorer La Salle. At the time of its sinking, the La Belle had a supply of hand-thrown explosive devices. These consisted of a hollow cast iron sphere placed inside a small ceramic pot, likely with more gunpowder between the two. The pot, which had a small handle, was plugged with a piece of cork, with a fuse running through the plug into the iron sphere. The handle made for easy throwing, and the fragile ceramic could shatter on impact, all but guaranteeing a successful ignition of the powder within. The result was a shower of both ceramic and iron fragments hurtling from the device at up to 200 meters per second.

In the test detailed in the link above, they found that the shockwave from the device exploding alone would almost certainly kill anyone within three meters of the blast, rupturing their lungs and other internal organs. The iron grenades created fairly few fragments, but a hit from one could likely cause catastrophic amputation. One plywood target was struck in the knee by an iron fragment traveling at 67 m/s. The fragment blew the knee 30 meters straight back carried on for another 75 meters before landing. Such an impact likely would have severed a human leg at the impact point. Ceramic fragments, while less powerful individually, were far more numerous, and still powerful enough to embed themselves in plywood within five meters of the grenade.

Source:

James E. Bruseth, Amy A. Borgens, Bradford M. Jones, Eric D. Ray, La Belle: Archaeology of a Seventeenth-Century Ship of New World Colonization