This will allow weapons to chamber ammo when the player has less ammo then set in the Add Chamber Amount, so for example you can set the Add Chamber Amount to 30 and if the player only has 15 of the ammo item, then 15 will be added to the weapon.
Warning this hasn’t been fully tested yet so you may have issues as this isn’t how the chamber system was built to function I suggest backing up your project before following this. This is not an official modification so if you have issues as a result of this modification you will need to resolve them yourself.
Copy the video below, this is in the BP_PlayerInventory in the Search Player Inventory For Multi Items function.
Next add the highlighted nodes shown in the image below, location at the top of the screenshot.
Next in the BP_MasterRangeWeapon you must create a new variable called Chamber Items and set its variable type to S_InvSlot and set it to an array (If you dont know how to set a variable to an array copy the video below)
Next go to the location shown in the image below and modify the code in your project to look like the code shown in the image below.
You can now set the Add Chamber Amount and Max Ammo value in the weapon holdable class defaults to what ever value you like, such as 30 for both, this will mean the character will try and load 30 ammo into the weapon and if less was found it will load that amount instead.