Hammershot shotgun cylinder.

thingiverse

Here's a modified version of the 8 dart cylinder designed for launching two half darts simultaneously. This uncompensated piece is specifically engineered to work in tandem with minimized hammershots, requiring the use of supports on the cylinder at all times. Compatibility is limited to upgraded springs; the standard spring lacks sufficient force to propel the increased mass effectively. A firing demonstration can be viewed here: https://youtu.be/pBC6tCxjrak (the blaster used features a 9kg spring with no air restrictor).