Don't feel toooo bad Englishman. EVERY weapon that ever left our Armourers shops or ANY Armourers shop across the Commonwealth was a 'parts' gun. Because by definition, they only ever came in because there was something wrong with them. And when they went out, they were fixed. Generally with parts, off the shelf. Ok, ok, so we accurately hand fitted them correctly. We weren't as careful as you about marking them of course. We tested them and off they went. That's the nature of the beast!