Which gauge for a smooth bore

[hogtracer]

Dear sir
Here in my place, no rifling options for muzzle loaders, Only choice is a smooth bore shotgun.I want to know from you seniors that which gauge barrel is ideal for an all around shotgun.I want it for shooting round ball and shots. Licensed only for crop protection. Hunting is prohibited. My biggest problem is from big wild boars.choice is in between 12,16, or a 20 gauge cylinder(only) bore doubles or singles.
                                                                                                                                               Thanking you all.

[Daryl]

I would go with a 16 bore. The 1 ounce ball is sufficient for big game (.648"round ball in a .662" bore with cloth patch), ie: hogs and it will handle shot much better than a smaller bored gun like a 20 bore. 

There is a reason there were more 16 bores built by Husqvarna & other European makers than any other size. They worked perfectly well and did not kick you into tomorrow with a lot of shooting.

[Robby]

I agree with Daryl, I have made and used all three gauges and prefer the 16 by a wide margin.
Robby