The difference between Handgun and Pistol is that although the Handgun has Medium Range compared to the pistols Short Range, it is balanced out by the fact that the Handgun is Two-Handed.

This difference seems to be missing when it comes to the repeater versions of the same weapons:

Repeater Handgun suddenly seems to be missing its Two-Handed quality, which i presume is a misprint..? (it doesnt really make sense that it suddenly becomes a one-handed weapon just by adding some repeater mechanism to it, making the Repeater Pistol useless in the process..)