Jim, my surprise doesn't go for the carrying along this gun. A healthy man (not an old dude like us both) can easily carry 40 pounds on his shoulder; not to mention they had the mules to do it. Besides, it is plausible that Coronado, leaving men behind to fortify some spots, had them equiped with such useful wall guns, not yet so anachronic due to its earlier generation, as you well suggest.
What intrigues is this mixing between
haquebuts (wall guns) typology and
versos (from the Portuguese berços) which is completely another thing; berços are breach loaders, for a start.
I ignore whether the article author was advised by metallurgists, as to infer that the lack of lead made the gun to have been cast in the New World. I heard that lead is only a small (if ever) fraction of bronze composition.
Doesn't it look more likely that these guns were shipped from Spain with the Coronado arsenal ?
Appologies for my ignaro approach

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