Module Switching Framework (MSF) - Updated

MSF has the ability to attach and remove mods (OMODs) to inventory items during gameplay. Data for equipped items is updated seamlessly with no visual errors. Features include ammo switching, selective fire, under-barrel, side aiming, and more. Also included are custom HUD widgets for ammo type and firing mode display. Supports BCR and TR.

Original address:

Prefix:

Fallout 4 Script Extender (F4SE)：

Mod Configuration Menu（MCM）：

Updated to version 1.2.8 on July 29th

Updated to version 1.2.7 on July 2nd

Updated to version 1.2.5 on March 24th

Updated to version 1.2.3 on January 11, 2026

*It’s okay to update on GitHub*

Chinese address:

Standard moderator files (supports 163) and next-gen moderator files (supports anniversary upgrades) have been uploaded. Choose one of the two to install according to your own game version.

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introduce

WARNING***This mod is experimental and may affect game save security and may cause stability issues. Use at your own risk.

The framework enables attaching and removing mods (OMODs) to the inventory during gameplay without the need for a workbench. Equipped item data (stats, animated charts, models, etc.) updates correctly and seamlessly without unnecessary animations or visual errors. Additionally, custom animations can be used before mods switch. Ammo switching and other types of mods use separate methods, which makes ammo switching only dependent on the currently equipped ammo and independent of the actual weapon (custom weapons do not require a patch).

Features

MSF is a framework that does very little on its own, you have to install other mods to add new features using this framework. Some demo mods are already available (Ammunition Overhaul and Service Rifle Lower Barrel and Selective Fire).

Ammunition Selection: You can change the ammo used by your weapon during gameplay. You can select/equip ammo type using 3 different methods:

Selection via hotkeys: Each ammo subtype (hollow point, incendiary, explosive, etc.) has an ID 2-9, where 1 is the base ammo; you can assign a separate hotkey to each ID (e.g. numeric keypad 1-9)

Ammo Loop: Cycle through each ammo subtype (reload animation plays each time)

Ammo Shortcuts: By cycling through each ammo subtype, selecting the target ammo on the HUD widget will equip the currently selected ammo type after a customizable timeout delay

Via UI widget selection: You can install a custom widget and assign a hotkey to it; when pressed, the available ammo options should appear on the HUD so you can select the desired ammo

Selection via Pipboy: You can equip ammo subtypes by clicking on them in the Pipboy menu

Mod Selection: There are 4 predefined mod categories (shooting mode, under barrel, muzzle, scope (e.g. side aiming)) and you can assign hotkeys to each category. Mod authors can also add new categories using new hotkeys. You can use two different methods to attach/remove Object Mods (OMODs) to your items during gameplay:

Assign a direct hotkey to a category to cycle through modules (loop example: semi-auto --> burst mode --> full auto --> repeat)

QuickKey Features: By cycling through each Mod in a category, selecting the target Mod on the HUD widget will equip the currently selected Mod after a customizable timeout delay

Install a custom widget and assign it a hotkey to display all available mods in that category

Supported loose mods can be equipped in Pipboy

HUD information widget: can display the current ammunition type, shooting mode, muzzle, scope; this module comes pre-installed with a basic widget, but you can replace it with a custom widget at any time. You can customize widgets in MCM.

Ammo capacity and reload count shown in weapon inventory menu (currently only in Pip-Boy)

Weapon status is now saved: when equipping a weapon (or changing from/back from under the barrel), the last ammo loaded should be displayed correctly (in the vanilla game, unarming and re-arming the weapon or changing weapons would reset the l …