looking at getting some salsa cowchippers for my drop bar hybrid/ adventure gravel racer / cx stylee – local salsa stockist has none so its online

currently have 42cm straight drop Eastons

Salsa says this on website:

“40,42,44, and 46cm sizes avalable (measured center to center)”

am i right in thinking that the hoods will move in if i buy another 42cm bar? (I like them where they are)

or do i need to buy a wider bar to get the benefit of the flare and keep hood in similar position? (and remember at narrow gates that I’ve changed the bars!)

I would stick with 42cm, use the extra flare for added leverage when needs be.
C-C should mean hoods stay approx. same position (depends where you place yours hoods I guess), but added width after a while becomes tiring, so would advise against moving up to 44cm e.g.

not the best of sketches (99.9% of STW users could do better)
but this is what I mean – assuming I’m correct that centre to centre is centre of the drop so this means hoods move in? as position is sort of fixed at end of horizontal

Your assumption is incorrect. 42cm is the width of the bars where the levers are fitted. The flare makes them wider than that.

cheers – that makes sense to me with the quoted available sizes

centre to centre means centre to centre at the top of the bar not at the flared ends