Any of the "engineering-grade" materials (PA6-CF, PA612-CF, PA12-CF, PPA-CF, PPS-CF, etc.) can work well for suppressors assuming:
- Your printer can handle them.
- You can properly dry the filament (drying at > 80 °C).
- You get the print settings right.
- You can properly anneal the parts (annealing dry at > 100 °C).
Technically, achieving good layer adhesion is the biggest challenge. You need a somewhat controlled environment so you don't overcool the layers and you need a printer that can maintain extrusion temperatures of 300 °C or more with margin. Process-wise, people often try to take shortcuts on drying and annealing resulting in poor strength and lack of heat tolerance.
What you'll get with the advanced materials is reduced baffle erosion thanks to the greatly improved heat tolerance. But it's still fairly easy to melt one down with high-volume, high-rate fire.