I'm in the market for a new halter, as the one my mare has is pretty old and starting to show the wear-and-tear. Plus, I've always thought it is too big for her (noseband too big & sits too low on her?). The picture below shows the size of the noseband, though the way she's standing on the cross-ties, it doesn't necessarily look like it's sitting as low on her nose as it does without the tension from the cross-ties.
I'm partial to leather, and was going to get a cob-sized leather halter (she's a 14.3 Morgan, and cob sized in other things like flymasks, bridles). Someone told me that leather halters tend to "shrink" when they're allowed to get wet and can become uncomfortable on the horse's head. Is this true? It makes sense to me, but the leather halter she's had for awhile now is ancient, and it came with her so I don't know how big it was when it was new (it's been through lots of baths, rainstorms, etc.- it's meant to be her one and only halter). How much shrinkage would you typically expect- enough to go with a new horse sized halter rather than cob-sized?