The Mexican gunpowder dilemma

[fernando]

Originally Posted by Jim McDougall

...WHY was Mexican gun powder so bad?

Specially taking into account that the invention was brought there by the Spanish Cortez early in the XVI century; and the joy shown in his letters to the Spanish King, due to the abundance of the necessary ingredients in local lands. I would take it as implicit that "cousin" fireworks was a tradition also brought by the Spaniards. It is not hard to realize that gunpowder takes more care to fabricate, but i would hardly digest the fact that preparing fireworks powder is a simple thing to achieve. One does not wake up in the morning and go to basement to fix some pyrotechnics only by reading the users manual; and eventually the risk to kick the bucket by mishandling the components appears to be the same in both cases.
Picture 1; an extract of Hernan Cortez report.
Picture 2 & 3; courtesy American Museum of Natural History.
Picture 4; How Goya saw the Spaniards performing the making of gunpowder.
Picture 5; The XVI century flour mill Molino del Rey in Mexico city, where next to it was the "old gunpowder mill".
Picture 6; a detail of the pavement in the pateo of the old (now museum) Portuguese black powder mill of Barcarena, where the bricks are positioned in "cleaver" and "spine", to avoid the risk of sparks by friction.


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[Jim McDougall]

Thank you Fernando, very well illustrated.
I agree, it must not have been a simple thing to do in making gunpowder, or why would there be such a struggle to import or obtain it from sources other than their own homemade concoctions.

Throughout the Mexican campaigns from the Texian revolt to the Mexican American war descriptions of the inadequacy of Mexican powder prevail. This was in artillery as well as firearms. In colonial New Spain, it was made clear that the use of the lance prevailed due to either shortages of or inadequacy of gunpowder. The reason Mexicans became so adept with lances was because they used them for hunting as well as for military purposes.

Interesting to see the example of a flour mill next to a gunpowder mill I guess two incredibly important commodities.

Interesting too seeing the bricks placed in a manner to avoid sparks, sounds like very prudent engineers.

[fernando]

I must have put it wrong in trying to establish the relation between 'fireworks powder' and 'gun powder'. In that between one and the other there isn't such an interval of knowledge. I wonder whether a gun powder craftsman is able to prepare fireworks powder just by his experience without any new learning.
On the other hand, i have now learnt that, while gun powder was brought to Mexico as early as in the era of conquistadors, fireworks also went from Europe but as late as in the XIX century.

I gather that the use of the lance, such an ancient reliable weapon as it is, was not an alternative weapon for Mexicans specifically caused by bad gunpowder issues. It has been a long way before firearms were so reliable as to convince armies to abandon lances and other white arms ... all over the globe. A humid 'good' gunpowder or a 'soaked' flint (or even a percussion) musket/rifle would let you down in the more critical of occasions; something you Jim have often approached.

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[yulzari]

Just to emphasise, the making of firework powder is comparatively easy. Good firearms powder is another matter.

Ordinary charcoal is hardwood charred in a covered pit or chamber at a high temperature. Good firearms powder requires lightweight woods, charred in a temperature controlled sealed burn at a low temperature with the other products of combustion removed during the process but retaining the fouling softening creosotes. Then ball milled to an impalpable dust and it can then be used. Termed a meal powder.

Delivered sulphur contains assorted contaminants and good performance requires it to be melted and the light contaminants skimmed off or left and the heavy ones left behind as the middle liquid is drawn off, cooled, broken and ball milled as above.

The saltpetre is even more contaminated and needs to be put into solution and crystallised. Perhaps several times to get a near pure result. Then again ball milled etc.

After the same mixing as firework powder it is put into expensive powered rolling mills (weighing tons) under careful controls and mechanically incorporated under these many tons of pressure for several hours. The longer the better. Then it is dampened and pressed at high pressure until it forms a hard cake. Once dried out the cake is broken up and then milled into chosen size grains. Said grains aresubject to being rolled loose to glaze the grains. All the the dust is removed and returned to be used in the next batch. Only them is it fit to be used as dense smooth grains. There are variations in wood, temperature of burn, length of milling time, density of the cake pressing, the size of the grains and general variations in the quality of the ingredients including the water used to dampen the powder for milling and for caking. Today one can buy firearms powder of a period 'musket' standard, 'rifle' powder and rarely a true 'sporting' powder to match rifle standards as in the late 19th century. Even in those days they could be tailored to give burning at chosen temperature. In one case a proportion of the fine charcoal was mixed with 30% charred peas so as to reduce the temperature of the burn to prevent the fouling being too hard in certain cases. The modern Aubonne works uses more saltpetre in their powder than normal which reduces the gas production slightly but increases the adiabatic expansion of those hot gases to give a better and more constant burn.

I mention all of this to show how hard it is to make a good firearm powder of even 'musket' powder standard and needs a customer willing to pay a far higher price than the minimum and an industry willing and able to invest in the capital and skilled staff to achieve it. The British experience of their suppliers in the ARW led them to demand higher standards and to invest heavily in the means to make it thus. French powder, at that time, was far better and made in government mills built to make good powder. If it took Britain until the Napoleonic wars to make the change and I doubt if Mexico had either the means, the will or the government culture to do the same only 20 yers later.

I will mention that meal powder can be corned, badly, with lighter pressure and little milling, even in a stamp mill by simply grating of the lightly pressed, or just dried, cake and passing the gratings through chosen sieves but the result is soft and prone to crumble in storage and transport. In which case the powder will need to be remixed or good grains separated from the crumbled dust. Gun powder is a very complex substance from which to get the best results. By the end of the use of gun powder in small arms it was moving into solid rods with assorted shaped holes to adjust the rate of burn so there was a collective sigh of relief when smokeless nitro powders were introduced.

[fernando]

Yulzari, let me bow to your knowledge. Being that i am only playing by ear, just to give a fight to Jim , i don't stand a chance to mess with your expertise. The thing is that we find a zillion works out there on the problematics of powder but never a comparison (technical or not) between the various powder products, in what touches their difficulty degree of preparation. All i can reach is that, the mill that makes powder for guns is able to make it for all less demanding purposes; such is the case of the main Portuguese powder factory. Previously the Royal armoury smithy, started making black powder in 1729, with four limestone galgas (mills), later replaced by wooden ones, with bronze hoops, containing in their interior metallic spheres to add weight to the setups, still making them more maneuverable; an invention with a replica now exhibited in the factory museum. Powered by the nearby water stream; modified to steam power in 1879, to electricity in 1920, diesel in 1924 and finally a hydro-electric group. It is to believe that the Portuguese could make a decent gunpowder since early days, judging by period chronicles. Yet in these facilities they produced powder ('pólvora') for hunting, mining, quarry, cannon, signals, and artifice fire (fireworks). Even when the factory started producing chemical powder in the 1940 decade, they maintained the fabrication of foguetes (firecrackers) and luminous artifices.


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[yulzari]

Indeed the technology existed for the Mexicans to make good powder had they decided to do so but the performance of the Mexican small arms and artillery as described in the Alamo and later war demonstrates that they did not choose to do so. Possibly they imported some good powder for their rifles. I have noted no rifle references in the commentaries.

The behaviour of the Mexican arms displays all the signs of poor powder. The Portuguese government mills shows how it could have been done. The Portuguese army had become accustomed to British powder in the Peninsula campaign with the extensive material support from Britain and was regarded as a very competent and reliable ally.

Tultepc by Mexico City has been a firework manufacturing centre for th past 200 years since Mexican independence and the end of the Spanish Royal gunpowder monopoly so Mexico did indeed make it's own gun powder in the relevant period, both for fireworks and blasting powder for mining.

BTW I notice that period Mexican gun flints found in Tucson were old French ones.

[fernando]

Portuguese were accustomed to gunpowder over four centuries before the Peninsular war, whether learnt from the British or whomever. Such is evidenced in history, based on countless artillery contacts. I don't think they would go as far as they did with low ratio gunpowder.

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[fernando]

Hoping not to be boring but, this is the first time i read of Mexican gunpowder grade being put in concrete terms, rather than just bad, poor or mediocre.
I have extracted a couple of (hopefuly) interesting paragraphs from the work "Finding A Face: El Soldado Mexicano 1835-1848" by Kevin R. Young, Historian (San Antonio, Texas).
I hope the PDF i have created is amenable.

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