Terminus by ShoelessHistorian

Terminus is two very comfortable 250 fps blasters fused together. Two barrels, two mags two independent triggers, one pump. While it's a bit heavier over a blaster, the ability to double tap is extremely good for gameplay and very satisfying for plinking. 

Hardware Only - Includes two 45cm barrels of 12.8mm inner diameter and two 6.66 inch 788 springs. All required hardware other than your choice of lube. 

DIY Kit - Everything in the hardware kit as well as all prints needed. 

Check out the printables here:

https://www.printables.com/model/1498126-flp-10-terminus-double-barrel-pump-action-foam-bla

Check out my print file here: 

https://makerworld.com/en/models/2058154-terminus-by-shoelesshistorian#profileId-2221851