When entering guns into ArmoryBook the recommended way has always been to select the Add option on the Guns menu. The information entered in the Acquisition Information section would also be available under the Purchases menu option on the Guns menu.
If a gun purchase was entered directly into the Purchases section there was no way to "convert" the purchase to a system gun. This process has been changed. Now if a gun purchase is entered using the purchase menu option, it will automatically be converted into a system gun once the status of the purchased is changed to Completed. If there is no Order Received date, the system will automatically enter the current date.
Once the purchase is saved, the system will go into edit mode on the newly entered gun, allowing the information that was not converted to be entered.