UPDATE V2: Added small indents on each side of the barrel to give the darts more space to stick out.
This is a remix of deusnefum's uncompensated hammershot mod that's made to work with hitchhiker4200's in-line cylinder. There is also a remix of the “blank fill” from the uncompensated mod with a Nerf N-strike rail. Warning: the Nerf rail is backward (that's the only way it would work). It's a little rough but it looks fine and it works. If you want instructions view the remixed models.
Happy printing!
The author remixed this model.