Steel cannonball

Steel Cannonball is a members-only item on the OSRS Grand Exchange in the bars category.

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

It has a Grand Exchange buy limit of 11,000 every four hours, a high alchemy value of 3 gp, and item ID 2.

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Steel Cannonball shows an active flip setup with a margin of +9 gp and 29,416,348 trades over the last 24 hours.

At the buy limit of 11,000 every four hours, max profit per cycle is about 99.0k gp — high margin with healthy liquidity.