The problem here is that armor piercing rounds need to be made of heavy metals in order to work and heavy metals are generally toxic. Even lead, which old fashioned bullets and shells are made of is toxic.
Uranium is more likely to distribute that toxicity in a convenient dust cloud, though. Tungsten and lead for the most part stay in one piece on impact.
Perhaps I should have said "not outrageously toxic" or something of that sort, because that does not sound worse than the stuff we make normal bullets out of - lead.
That's true! Lead does tend to stay more clumped up than uranium dust. But isn't it also easier for lead to become bioavailable and/or enter the water supply?
https://www.atsdr.cdc.gov/toxprofiles/tp186.pdf
The problem here is that armor piercing rounds need to be made of heavy metals in order to work and heavy metals are generally toxic. Even lead, which old fashioned bullets and shells are made of is toxic.