Thanks for the responses. From the limited information I have come across, V-C patented a triple locking action similar to the Webley action in the early 1900s called the Helice grip. It was modified/improved over time and had various names including Helicobloc and Heli 33. VC let the patent expire for some reason and other French makers used it and often marked their guns with similar names - Helico, Helistop, Helicogrip. There are some patent diagrams posted on this link (en Francais, bien sur)

Gournet

Larry - thanks for the tip on reaching out to VC, that sounds worthwhile.

Here is a photo of the proof marks:

Last edited by Doverham; 10/24/12 10:47 AM.
Such a long, long time to be gone, and a short time to be there.