aroma
521
Co-Ax calibre 2403 - any info???
Hi All,
I’ve been looking at buying a used Co-Ax Railmaster (as I'll need a mortgage for a CK-2914!!) and am somewhat confused by the info I’ve found. I’ve been doing some research into the movement as I know that examples of the earlier Co-Ax movements did suffer from problems.
The RM I’ve been looking at uses a calibre 2403. Apparently, the base calibre for this movement is the ETA 2892-A2 with the Co-Ax escapement replacing the traditional lever escapement. The 2403 came in two flavours namely the 2403A and the 2403B.
The original calibre 2403A had a high beat rate of 28,800bph but Omega reduced this to 25200bph for the 2403B as they felt that the Co-Ax escapement would not last too well with the high beat.
Obviously, I would avoid a watch with a 2403A movement but how can you tell from looking (the movement is stamped just 2403) and I was wondering if any of you have experience with early Co-Ax calibres.
As always, any thoughts are appreciated.
Cheers
Andrew
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