I've just started the game to check this (as I still have it installed). There is no key setting in the game's interface for reload, and by pistol I'm assuming you mean the automag.
There are two fire modes, primary and alternate. For the automag the primary is a standard shot (hoold down for repeated shots) and the alternate is increased firing rate at a cost of slightly less accuracy, whereby the gun is held sideways (gangsta style as you put it).
Note that the HUD shows no number for rounds left in the clip, only the total number of rounds left. So you'd not know when to reload either. The reload time for the automag is very fast anyway.
Also, considering how the other weapons also work, it does tie up with no reload function. There doesn't appear to be a reload function in the ini files either.

Reloading is not available in the default Unreal game.
If you play Unreal through Unreal Tournament using the Oldskool mod by Usaar then you can bind reloading to a key and use it. Other benefits of Oldskool:
Permanent carcasses and bloodstains
Unreal1 weapons-pickups in UT maps / UT weapons-pickups in Unreal SP