Symbolism, Imagery, Allegory
Take one look at Anton Chigurh's silenced shotgun in No Country for Old Men and you'll realize that Cormac McCarthy has a bit of a thing for powerful guns. In the early going of Blood Meridian, McCarthy celebrates the craftsmanship of some custom-made pistols that Glanton wants to buy for his gang. As the narrator says:
These pistols would drive the half-ounce conical ball through six inches of hardwood and there were four dozen of them in the case. (7.2)
According to McCarthy, these pistols don't just penetrate their target. They make it not exist anymore.
You see McCarthy's fascination with powerful guns again later in the book when he talks about a howitzer that Glanton's men like to play with:
They loaded the howitzer that evening with something like a pound of powder and the entire cast of shot. (19.2)
Like a shotgun, this howitzer shoots a bunch of tiny ball bearing-sized pellets. As you can probably imagine, everything that isn't standing behind this gun gets wiped out.