When the Texians ejected Perfecto de Cos and the Centralists from San Antonio, they made an inventory 13 Dec. 1835 and at first mis-identified the pedrero as a "culverin." It is a weird gun. It basically used stone shot, and so it typically had a large-ish bore, but thin walls. It also used a smaller powder charge, a bit like a howitzer or "obus" in Spanish. It has since disappeared without a trace... One the missing guns. It seems that an inventory made by the Mexican forces accounted for 75 stone balls for it and a "box" or "bote de metralla" of musket balls. https://www.thealamo.org/remember/savethealamo/digitalbattlefield/index.html Incidentally, the Mexicans itemized weapons and ammunition taken from the Alamo after the battle. They enumerated 816 firelocks, so each defender had something like three and even four guns at his disposal. Unfortunately, they left no indication how many were double-barrel muskets (like that of Travis), or muskets, or long rifles. The one firearm with Alamo provenance appears to be a fine Jacob Dickert, Lancaster Pennsylvania rifle, which has been written about by Texas Monthly and is on display at the Alamo. Researchers suggest that a good many of the New Orleans Greys acquired Model 1817 Common Rifles, .54 cal. Lots of muzzle loading artillery enthusiasts come out to the Alamo in the last weekend of September/ first weekend in October for "Cannon Fest." Not much shooting, but lots of guns on display, and discussions of the cannon... A great event! I've been privileged to attend the past two years as an assistant matross... Please note that the guns listed on the map are decidedly inaccurately sited and listed... The list I posted earlier has the current thinking on where the guns were... At least three of course were simply without carriages laying around... As may be seen, the Alamo compound was simply too large to be adequately defended, and while there were many cannon, it required a lot of crew to be able to serve the guns. The Mexican artillery included several "7-pulgada" howitzers (about 6-1/4 to 6-1/2 English/U.S. inches) that fired many exploding case shot shells into the compound, which is written about by Travis. Most Mexican artillery pieces were 4-pounders.