We have been working with the horizontal pellet dispensing design of FED since 2016, but while stuck at home during the Spring of 2020 I started experimenting with a completely different pellet dispensing approach, using an angled dispenser.  This dispenser is much less likely to jam, and we've switched over completely to these in my lab.  Here's a demo of how it works:

The 3D files and more info can be found at the FED3 Github site.