With this image of the 26.5 you can see there is some space between the mast head and the top of the sail headboard.
You can take the sail down and measure the luff to compare the size of the sail luffs. Here are the sail measurements.
Save on Standard Sized Hunter 26.5 MainsailBuilt to the same exacting standards as our custom sails and featuring a comprehensive list of standard features. IMPORTANT: Please tell us whether you wa...
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30ft 10in for the mainsail.
Sail boats classes set a specific height for the sail. That is why you will find a black line at the top of the mast to indicate where the sail is intended to reach.
You may have another issue, other than the sail length. The location of the goose neck may be too low. (Gooseneck the fitting on the boom that connects the boom to the mast.)