This mod is COMPATIBLE WITH BEAUTIFUL DOOM v. 5.0 (older versions will work not properly), but it doesn't require it, Russian Arsenal can work standalone as well. As the title implies, it's just a set of Russian firearms. And they don't look too hot. But they work. But note, that weapons with low accuracy CAN NOT be used for sniping, because low accuracy applies to each and every shot, including the first one (unlike usually in Doom), except AK-74 (its single shots are accurate). Check weapdesc.txt for more information. There's also detailed description of the guns inside DECORATE lump in the wad.
FPSBANANA 3d-modellers for weapon models which were used to make sprites
New from scratch with some resources: FPSBANANA models ww-diaz (I think, some weapon sounds) something else