Can you shoot slugs with a High Standard Field Classic 12GA with serial number 3115127?

The answer is Yes. You can fire any NON-Rifled slugs out of this gun. I have the same model #3178094 and I have fired many kinds of slugs from this gun. You have whats called a smooth bore shotgun which means you can fire any slugs or projectiles made for smooth bore. when you buy your ammo ask the gun shop to show you what I'm talking about. When you look inside the barrel you see it's smooth. The slugs you buy have a plastic case around them so the lead never really comes in contact with the inside of the barrel. Some shotguns have a rifled barrel which has spiral grooves in it the same as a handgun or rifle barrel. A rifled slug rides in the grooves of the barrel just like the bullet of a handgun or rifle. .I hope this helps you understand a little bit more about this gun.