I don't know. The Mexican and French were pretty stiff about shipping guns and artillery through Matamoras. There is testimony that the Texans had made some lighter runs directly from Confederate territory to the Pell, who knows what they brought back? Most of the rifles brought in came in through Velasco or Galveston. I haven't seen anything specific about artillery. A 6-pounder was pretty light for anti-ship work, but rifled guns did have an advantage in terms of range.