These resin castings are provided in the unfinished condition and are cast in high quality polyurethane resin. They can be drilled, cut and sanded with care.  When working with any type of resin, care must be taken since the fine dust produced with sanding can causes irritation.  We recommend using wet sand paper to avoid this problem.  

Fairly recently added are some brass barrels.  These are designed to replace kit barrels for a better look and will be more robust.