Based on
cannelure's root word, you would think a
crimp groove and a
cannelure (the root word is an old one meaning
channel) would be the same thing. But where
crimp groove applies only to bullets,
cannelure is not limited to the bullet.
A
crimp groove is an actual recess molded or rolled into a bullet that goes all around the bullet the way a lube groove does, except that it is usually a tapered profile to roughly match the shape of a crimped-over case mouth that would be turned into it.
A cannelure is a groove with a tiny gear-tooth-like pattern floor that is rolled into a jacketed bullet or into a case, as you sometimes see in revolver cartridges where it marks the original commercially loaded bullet base's location. The military also put one around the head of M852 match ammo back when the hollow point Sierra MatchKings were not approved for combat, thus to make it easy to see it was non-combat ammunition. The SAAMI glossary describes the cannelure's appearance as corrugated, which works, too:
Quote:
|
Originally Posted by SAAMI
CANNELURE
1. A circumferential groove generally of corrugated appearance cut or impressed into a bullet or cartridge case
2. Sometimes used in reference to an extractor groove.
|