No idea what they are but I imagine bullets would do a lot more damage to brick than that. And there a strange pattern that doesn't make sense for bullets.
A person made these marks, they all kind of focused towards a center line, overall. Maybe a rock hammer? Is especially obvious on the bottom third of the picture with the arcs in the patterns.
The real question is "Are they like that all the way through, and if so, how much, precisely, would that affect the strength and insulation as compared to 3 hole red brick?".
Yes, i know bricks have a different amount of holes depending on where they're made already, don't go there, it's settled.