Campagnolo Freehub Lockrings

[Jesper]

I am trying to use a wheelset that has a Campagnolo Veloce freehub with an alloy body. I do not know what year the hub is. As I installed a Veloce 8 speed cassette (fits perfectly) I could not get the lockring to thread onto the hub. I thought I had too many cogs on the hub for some reason, but no; 8 spd hub and 8 cogs.
What I found was that the lockring was larger in diameter than the freehub body threading. I had not run into this problem before, probably due to not swapping out parts or running many freehubs on my wheels, but I had purchased the wheelset assuming my cassette would fit (which it does) without any issues. I do not know what year the cassette is either, but I suspect the cassette is older than the hub.
While doing some research I discovered that Campy used 5 different sized lockrings; 3 with different thread O.D.'s and 2 different flange diameters.

29.0mm
Supposedly, the 29.0mm outside diameter ring is for cassettes starting with a 12T cog or larger, and used only on 8 spd steel body freehubs. The ring will not fit Campy Record 8 spd freehubs having an alloy body and that came with titanium cogs; that freehub uses the 26mm O.D. ring that also fits early (1997) 9 spd units.

26.0mm
The 26.0mm O.D. ring has 2 flange sizes which are used dependent on what starting small cog is fitted. If 12T or larger than the 38.5mm flanged ring must be used, and it is not interchangeable with the 11T cog set-up which uses a ring with a 35.2mm flange diameter. both rings are designed to fit 9 speed freehubs ('97 &'98 Record, Chorus, Athena, Veloce, and Mirage 9 spd hubs), and all factory built wheels w/9 spd hubs of the same time frame. Fits '99 Athena, Veloce, and Mirage 9 spd hubs. All Campy 9 spd hubs will also fit a 10 spd cassette.

27.0mm
A 27.0mm O.D. ring is used on Campy's "oversize" 9 & 10 spd hubs that appeared circa 1999. The ring's flange size (38.5mm or 35.2mm) is comparable to the 26.0mm ring dependent on if a 12T or 11T cog is used.

So I have an alloy freehub (presumably Veloce; the hub dust cap says "Veloce") and a Veloce cassette that fits the hub, but I don't know what ring size I need. I have not measured my ring, but I would assume it to be 27.0 or 29.0mm at this point. My small cog is 12T so I assume I will need the 38.5mm flanged ring to fit. I think I have another cassette that is loose so I will check the ring (if it's still with the cogs) compatibility with my hub set-up and provide whatever info I can as a future reference for others.

If anyone has experience with this and can shed some more light on the subject it would be greatly appreciated.

[Jesper]

I have measured the lockring's thread O.D. and flange diameter:
Thread= 29mm
Flange= 38.5mm

The hub's size is 27mm. I don't know if this indicates that the hub is of the "over-sized" style and circa '99 and later or not.
My small cog is 12T and the ring sets in it perfectly so it seems original to the cassette.

This would seem to indicate that a 27mm was also used on an 8 spd hub with an alloy body at some period in time.