In the current version, unfortunately not; I plan to look into a possible solution, e.g. a 'performance toggle' that downgrades its particles. Is it a constant FPS drop while firing, or just when doing specific things like killing enemies?
I've tossed together a possible solution, here's a quick test update that may or may not remedy the frame loss. It adds a new option for "fast" lasers with downgraded particles; let me know if this treats the issue. If so, I'll push it as a proper patch. If not, I'll continue tinkering.
The option is under "Visual Options" in this version.