This is a drop in replacement for the front end of the Rival Pilot. To install, put a 16x1.5mm o-ring (or any 1.5mm thick o-ring that fits) in the o-ring groove on the outside of the tube portion. Put this 3d-printed part inside the stock, rival ball accepting, breach (you will need to remove the hop-up). Then button up the blaster as normal.
This has 3 printed parts to it:
The inline mags may need to be sanded to ensure that they drop out the way you want them to. To load the inline mags, push 4 darts into the tapered opening at the top. The barrel shroud has an integrated Trivictus PCAR, which can be found here: https://www.thingiverse.com/thing:5174583
This mod also plays extremely nicely with the manual break action mod that can be found here: https://www.thingiverse.com/thing:5830514
Happy printing! If your inline clip gets stuck inside the barrel (it happens sometimes, I think it is genuinely dependent on humidity and temp) Unscrew the barrel shroud a bit, and it should drop right out.
The author remixed this model.