Note: If you get motion sickness, try +fov 85 instead. The default is ~75.

In the same launcher menu, manually select your monitor's native resolution (e.g., 1920x1080, 2560x1440, 3840x2160). Apply and close the launcher.

The gun models will still be enormous at high resolutions. To fix this, add this second command right after the FOV one (separate by a space):