So from what I gather, this is a copper-jacketed, smooth-sided slug with a lead (?) core? And it’s tapered like a bullet? And it’s got a 6.7 inch drop after 200 feet? I suppose that’s as close as you can get to a bullet’s trajectory with a large shotgun chamber.
I suspect the drop is actually at 200 yards, not 200 feet.
Ultimately, shotguns are not generally built as strongly as rifles, and if you want rifle performance, you’re going to have to get a rifle.