We Build Gun Collections. Rock Island Auction Company is the world’s top auction house specializing in antique and collector firearms. As our reputation for integrity, quality, and rarity has grown, so have our results. Thanks to our tireless work ethic and constant pursuit of excellence, we remain the largest auction house for antique firearms, collectors firearms, rare guns, modern guns, and other firearm related items since 2003. We continue to bring record prices and offer some of the most historic, rare, and rare guns you will find anywhere in the world.