Here's how it works:
* Paint is a *pattern*, not a color. Paint horses have a base coat color (usually bay, chestnut, or black) with white markings.
* Gray is a *color*, meaning the horse's coat is predominantly gray.
So, you can't breed two horses to make a "gray paint" in the same way you breed two specific breeds.
To get a paint horse with a gray coat, you would need:
* One parent with a gray coat: This could be a gray Quarter Horse, gray Thoroughbred, or any other breed that carries the gray gene.
* One parent with the paint pattern: This could be a Paint horse of any base color, as the pattern is determined by a different gene than the coat color.
The resulting foal would have a 50/50 chance of inheriting the gray gene and could be a gray paint horse.