273 Head Gaskets

Pulled the heads off my 273 for the first time in it's life and noticed that the head gaskets aren't round anymore like the cylinder bores, but rather misshapen. Any idea what might cause that?

Notice in the upper right hand corner Chrysler even stamped the penstar on their head gaskets.
IMG_2383.jpg

IMG_2384.JPG

IMG_2385.JPG