Bosal and mecate setup for long gathers

Quick question for those riding hackamore sunup to sundown: what bosal diameter and mecate weight are you using when there’s 10–15 miles of trot, gates, and a green but willing mind? I’m in a 5/8 rawhide with a 22’ horsehair mecate — nice feel and clean releases — but I’m getting a faint rub on the right nasal after hour four even with clean sweat and balm; debating a 1/2 with mohair wrap or a soft rope mecate to keep the cue alive without burning hide — what’s worked for you?

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I’d keep your 5/8 rawhide and trade the 22’ horsehair for a 9/16 mohair mecate — same clean release but it won’t saw on long trots, and it’s the one change that stopped a faint right-side rub cropping up at “hour four” for me. Does it spike after the right-hand gate work or stay constant the whole loop?

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Try one tiny fit change before swapping gear: shorten the hanger one hole on the right and roll the heel knot a thumb-width left so the 5/8 sits dead even; that fixed a faint right-side rub for me over 12–15 mile trots. @dane_elliot91’s mohair idea is solid, but if you love horsehair, stick a thin moleskin strip under the right nasal for the big miles. Is the rub right at the seam or just ahead of it?

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If it only shows up around ‘hour four’, I’d keep the 5/8 but go to a softer, oval nosebutton (rope- or soft-rawhide core) and add a thin chap-leather wrap for the long trot. That keeps the feel you like from the 22’ horsehair without the grit, and a touch more heel-knot weight helps it float instead of pressing the bridge. Is your nosebutton round and hard or already ovaled — if round, this write-up is solid: https://eclectic-horseman.com/hackamore-dos-and-donts/.

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