We have an FFL and use fiber lasers for gun work on any metal parts ... CO2 on wood stocks. If the part is composite/plastic we try to find an unseen spot to do a test mark, like the backside of a removable pistol grip.
Technically, the FFL isn't needed for the engraving - it's more about taking possession of the firearm.
Bill Collier
Arch Engraving
Fenton Missouri
-----------
Electrox Scorpion Galvo Fiber Laser
Epilog Fusion "Flying Optics" Fiber
Coletech Chinese Galvo Fiber
Epilog Fusion CO2
2 Epilog Mini CO2
Trotec Speedy 100 CO2
Xenetech XOT-1625 Rotary Engraver
Xenetech Viper Rotary Engraver
Sandblast cabinets: Trinco & Comco
Vinyl Plotter