This is a model of the muzzle-loading, smooth bore musket used by the Mexican infantry during the Texas Revolution. Of British origin, this third generation or “India Pattern” descended from a line of weapons that were used as early as 1722. A good discussion of this gun can be found in Arms of the Mexican Infantry 1835-1836.
My model was created in Blender and textured in Substance Painter. The render above is from Substance Painter.
You can view and explore this model in detail on Sketchfab