Forgive my ignorance, but in the video it showed the Bushmaster upper had a larger ejection port and a modified feed ramp to deal with the larger round. Would these changes, and perhaps similar changes for 7.62 x 39 or Valkyrie need to be done by Spectre prior to cerakoting, or could a gunsmith perform the modifications after the fact?
No changes needed for 224 Valkyrie. cant say for x39.