New model for the gun - Colt Python. Full metallic body with different color tones for every major part. Looks really well in-game. Check my profile for my other creations, comments and reviews are highly appreciated.
Rename the file as gun or shotgun, depending on which one you want to replace. Move it to steamapps\common\Teardown\data\vox\tool and replace with original file.
Always make backups of your original files!