The Submachine Gun (SMG) is not a craftable item, it is hidden in Hall 13. To reach it though will involve some work. This How to get the SMG in Remnant: From the Ashes will tell what needs to be done to get this weapon.
The Submachine Gun is a great weapon to have as it is able deal plenty of damage to enemies and bosses. In order to get hold of it you will need to get the access card on the first level and go to area B2 of Hall 13. Inside area B2 go to the back room to find the fuse, once you have the fuse go to area B3 and put it in the box to open the door, turn off the fuse box and then go through the fan duct and pick up the Ward 13 key that is on the desk. If you now return to area B2 you will be ble to use the key to open the door to the south where you can get the Submachine Gun that will be on a desk (see screenshot above).
Check out our How to get the Assault Rifle Guide in Remnant: From the Ashes to get this deadly mid-long range weapon.
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