Guns with ribs are easily sighted - red dots, scope or irons, my favourite. The scope and irons I've done myself, the scope only for load development, which worked flawlessly.

I used round balls, not slugs with both black powder and smokeless. Smokeless kicks about 1/3 the amount of BP - and with old gun, it's the best choice. My first few shots with 7 drams of black powder and an ounce and an eighth round ball cracked my stock through the wrist, although after being repaired, it stayed together with the same ammo. The equivalent velocity (1,550fps) with smokeless kicked no more than a 2 3/4" magnum shot load.

Shotshell manuals by Lyman of #3, #4 or #5 have data that can be used, or extropolated and worked up to using equivalent powders and wad columns, but be careful but if you haven't loaded shotshells before. In that case I suggest you stick with factory ammo, although it is inferior to a good round ball load. There is a lot of different ammo for shotguns available today, some being meant for rifled shotguns, others for smoothbores or both.

Good loads with round balls or slugs that your gun likes should stay within 4" at 60 yards. Most times a person has to try different ammo to find one that works in that particular gun.

For handloading round balls, if there is a trap range near by, collect a bag of spent trap wads. The ones with the hemispherical gas check on the bottom are the ones you want. Use side cutters and cut the gas check wads off the column and shot-cup. You want the gas check wad, 2 per reload. Buy some fiber wads, ie: 1/2" and you are set for wads for loading round balls. Balls from .680" to whatever your bore size is can be used in straight tubes. Lyman makes a cheap, $20.00 round bal mould in .690" which will work perfectly, or you can do as I did and have jeff Tanner make a few couple ball moulds, ie: .710", .722". About any alloy, like pure lead or WW metal can be used.

The gas checks, one down on the powder, then a filler wad, then another gas check is placed cup-up underneath the ball which keeps the ball centred in the bore during it's trip up the tube. The case can then, if wad height is adjusted properly, be fold crimped over the ball. Lee Shotshell reloading presses will work fine for this (I use one in 16 bore for my Husky's round ball loads with 2 1/2" brass cases) and an old heavy Herters bench mounted press for the 12 bores with plastic cases.

Here's a picture of round ball loads in brass cases for an old Husky 16 bore, the right barrel of which is straight rifled and 13 bore in size. Note the smiddle row of balls is cloth patched. I used undersized balls with a heavy denim patch. This ammo printed the best groups of all at my 30 yard range, all 7 shots going making a 1 1/2" hole, while the bare balls made a 2" pattern - quite suitable though. The gun has a V rear sight, with a bead on the front.

As to regulation, no one can tell what the gun will do, as point of impact may change with any change in loads. It's all part of the gun of developing loads for individual guns.