In this part of a Hank Jr. song, he uses "them" instead of "that", can someone explain me why did he use "them"?

Because you can't stamp us out, and you can't make us run, because we're them old boys raised on shotguns.

Them is plural and is used instead of the plural those. This is quite common in the English of uneducated people but is generally considered nonstandard and incorrect.

You can't learn ordinary conversational English by modeling yourself on song lyrics -- unless you wantto sound like you, too, are rough and tough, ignorant, and motivated by the basest passions, i.e., "raised on shotguns", and proud of it. In that case, you shouldn't be asking grammar questions on an English forum; it will ruin your image! Emotion: smile

Songs like this often paint a picture of a reality enhanced by the "local color" of substandard language. These pictures are mostly fictitious and present mostly minority groups and their supposed views.

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I know,I thought about don't write the part of the shotgun here, but I just asked it just because I didn't understand what he meant with the "them", I'm not modeling myself on these songs, don't worry Emotion: smile

And thank you Cool Breeze.
Students: Are you brave enough to let our tutors analyse your pronunciation?
makaayI'm not modeling myself on these songs, don't worry
That's a relief. Emotion: smile