Rune cannonball

Rune Cannonball is a members-only item on the OSRS Grand Exchange in the runes category.

In-game examine text: "Ammo suited for a boat's cannon."

It has a Grand Exchange buy limit of 11,000 every four hours, a high alchemy value of 840 gp, and item ID 31914.

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Rune Cannonball shows an active flip setup with a margin of +7 gp and 725,958 trades over the last 24 hours.

At the buy limit of 11,000 every four hours, max profit per cycle is about 77.0k gp — high margin with healthy liquidity.