Hi Larry,
You are right, but in the machining world, "rectifieuse" is and has always been a grinder as in surface grinder, centerless grinder, etc.,hence my translation.
I forgot a few things (at least):
pierrage=honing
demi-bloc= you guess
ejecteurs= ditto
crochets rapportes= non-integral lumps (same as encastres;
note that this *could* refer to shoe lumps as well, but I have never seen a French shoe lumped gun).
poudre vive= smokeless (in Belgium)
fabrication mecanique=machine fabrication (meaning interchangeable parts, industrial machining, rather than hand made, one of a kind)
arquebusier= gun maker and dealer
armurier= gun dealer
armurerie= gun shop
successeur = successor to
cannonier= barrel maker
fait pour= made for

Best regards,
WC-