Now that I look at it, the 1930 Revolution is a richer military topic. It lasted a couple weeks and was a multi-front civil war with the rebels taking large swathes of territory from the legalists, but right before a major battle was to take place a coup within the legalist side interrupted fighting and handed power to the rebels. The death toll was probably still very low, but not as much as the 1964 revolution which left only 7 dead, all of them civilians.
However it's even harder to find information on actual military movements in 1930.
There's also 1932, but that was lopsided with only a single state being in rebellion. Way earlier there's the Rio Grande do Sul independence war which lasted ten years and had the separatists invade and declare a republic in another state, build a navy and enlist Garibaldi to their side.