What art programs did you guys use to design the 3d models for guns in the original game?

I used cinema 4D with Octane renderer for the weapons, basic Cinema 4D renderer for the rest of the game

(there Octane provided too little shadowing and AO and the basic renderer worked much better, on the weapons Octane was much faster and gave better results however) That is an expensive combo however

For Synthetik 2 our weapon artist uses Blender but results are comparable with a bit of tweaking