It appears that the US Gov't, Captain Walker and the Texas Rangers wanted conicals to fight the Mexicans.
But perhaps more importantly to fight the indians.
The Texas-Indian wars started with the first settlers and lasted until 1875.
Wikipedia entries state that the use of revolvers turned the tide of the indian wars to the benefit of the settlers.
During the civil war, settlers were pushed back over 100 miles by the indians.
1821–1844
Up until the introduction of repeating rifles and revolvers, weapons and tactics were definitely on the side of the Plains Indians, most especially the Comanche. It was not until the
Battle of Bandera Pass, where revolvers were used for the first time against the Comanche, that the Texans began to gain a clear military advantage due to superior weaponry. Despite that disadvantage, it was disease and pure numbers which probably ended the Plains tribes.
1844–1875
By 1860, there were fewer than 8,000 Indians, and 600,000 Non-Indian colonists in Texas. The Texans further had access to repeating rifles and revolvers. Many military historians believe the defining moment in the Texas–Indian Wars came with the introduction of the revolver. In any event, pure numbers, better weapons, and brutal starvation tactics ended Plains Indians hold on to their homeland.
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The half-century struggle between the Plains tribes and the Texans became particularly intense after the Spanish, and then Mexicans, left power in Texas. The Republic of Texas, which had increasing settlement by European Americans, and the United States opposed the tribes. Their war with the Plains Indians was characterized by deep animosity, slaughter on both sides, and, in the end, near-total conquest of the Indians.
The Comanche were known as fierce warriors, with a reputation for looting, burning, murdering, and kidnapping as far south as Mexico City. When
Sul Ross rescued
Cynthia Ann Parker at Pease River, he observed that this event would be felt in every family in Texas, as every one had lost someone in the Indian Wars.
[2] During the
American Civil War, when the US Army was unavailable to protect the frontier, the Comanche and Kiowa pushed white settlements back more than 100 miles along the Texas frontier.
Texas-Indian Wars: --->>>
https://en.wikipedia.org/wiki/Texas–Indian_wars#1844–1875
Comanche power peaked in the 1840s when they conducted
large-scale raids hundreds of miles into Mexico proper, while also
warring against the Anglo-Americans and
Tejanos who had settled in
independent Texas. Their power declined as epidemics of
cholera and
smallpox inflicted severe casualties on their population, and as continuous pressure from the expanding population of the United States forced them to cede most of their tribal lands.
Commanche Wars: --->>>
https://en.wikipedia.org/wiki/Comanche_Wars
Map showing Commanche lands during the 1800's