I said Modified or MORE open, not a cylinder bore, which depending on the slugs you use might work well. I have actually had really good luck with a modified choke in both my guns. Both shoot slugs better with that choke and both my guns came with several and I tried them all.

It really depends on the overall diameter of the slug you pic, they all vary slightly from company to company. Inline muzzle loaders are the opposite, the barrels actually differ in size from manufacturer to manufacturer!

Getting an accurate slug gun takes some time and effort unless you get lucky right out of the gate.

I also have an H&R slugger for a dedicated slug gun and like it. If you decide to go that route though I would suggest the 20 ga ultra over the 12 ga. It is more versatile and from what I have seen will have better accuracy potential with the faster modern sabot bullets.

Paul