[Fox 6]

Personal Defense Weapons are actually a classification of firearm. Examples are the p90 and the HK MP7. They fire smaller caliber rounds with heavy penetrating power. I think the bullets rely more on their design and less on the materials. Plus Depleted Uranium seems to expensive for smaller caliber weapons. The GAU-8 Avenger on the A10 Thunderbolt however is the perfect platform and makes better use of its rounds when taking out tanks and such, or the Sabot rounds from most modern tanks.