Scraptrap Prime & Scraptrap Nest - Borderlands 3 Farming Guides
Location: The Compactor in The Handsome Jackpot
Part of: One Man's Treasure Story Quest (Moxxi's Heist DLC)
Drops: Boomer (Dahl SMG) and Lucky 7 (Jakobs Pistol)
The Scraptrap Nest which contains Scraptrap Prime and many Janky Scraptrap enemies can be found in the northwestern most portion of The Compactor zone which is on The Handsome Jackpot. This area is part of Borderlands 3's first DLC called Moxxi's Heist and can not be accessed unless you have this DLC purchased and installed.
As far as loot goes, Boomer (Dahl SMG) and Lucky 7 (Jakobs Pistol) are both on the Scraptrap Prime/Scraptrap Nest's dedicated loot list. Neither of these weapons are unique to this encounter and can be found elsewhere in The Handsome Jackpot as well.