While that's not my intention, if you actually wanted to damage satellites and cause a Kessler Syndrome scenario, it's hard to find a system that would have a bigger bang-for-your-buck.
I was rather envisioning a target satellite that is designed to absorb the pellet as an inelastic collision. It would probably resemble something like this: https://en.wikipedia.org/wiki/Black_body#/media/File:Black_b... . Of course, if it didn't work as designed, then it could be a problem.
The point was that a high altitude low-mass-per-shot gun system could get mass into orbit with a similar energy cost as a space elevator with significantly less upfront capital cost and no need for miracle materials.
