How to Unlock the Laser Minigun
To get the Laser Minigun plans means finding the Enclave Vault and joining their faction. The Enclave Vault is located in the southeast area of the map. Go to the Waste Dump on the eastern-most river on your map and search for a cave so you are able to begin the Enclave Faction quest. Once you have joined the Enclave by completing their quest which involves solving puzzles, destroying the robot guardian at Sugar Grove and retrieving a tape there you will have proven your loyalty and be able to access the Enclave Vault terminal. The Laser Minigun Plans are available for 1,000 caps.