Anyone know about this muzzleloading shotgun? What do you think about it? If anyone is willing to sell one, I might be interested.

Built by Armi San Marco and offered by Beretta. As with all ASM products some were good some were bad. Take your chances.
If you want my advice you're better off with an older Pedersoli SxS.

So - not actually a Beretta?

Did Beretta ever make a muzzleloader? If not, are there any Belgian made muzzleloaders for sale? I'm looking for a quality gun that will see regular use.

pedersoli is very good quality

Something like this?

http://www.gunsinternational.com/guns-fo...un_id=100880835

Or something like this?

https://www.davide-pedersoli.com/scheda-...uxe-cal-20.html

https://www.davide-pedersoli.com/scheda-...lish-maple.html

I only know of two and both soon started to suffer ignition problems which were difficult to fix being in over/under configuration. Lagopus.....

Back in the 80's when they first came out I looked at 3 of them at a local gun shop. The first two I handled would fire when the hammers were at half cock and the trigger pulled. The third one had no problem and I bought it.
I used it for years and never had a problem, it always went off. I have heard of problems with the lower barrel firing, but never experienced it.
It was a good handling, pretty lightweight shotgun. The ramrod is skinny as all get out, but it never broke.
80 grains f 2f powder and 1 oz of shot worked well on ducks, pheasants, bunnies and bushy tails.

Nice photo! Is this a gun that could safely handle a heavier load if weight was added to the stock?

I too have one and hunted ducks and grouse for years until steel became mandatory, now with the availability of bulk bismuth I thinks it is time to get it out in the blind. My BinL would get so pi--ed when I'd limit out with this before he did with his 1100. Never had any problems with it going off.

I bought this in the early 1980 and the wholesaler sent me two by mistake, I kept both and gave one to my other BinL and told him I wanted it back if he ever thought about selling it, he never said anything and ended up selling it for $200, I could have just kicked him.

I never saw the need for a heavier load as the 1oz does well. The gun does have VERY thin barrels, both barrels are cylinder with no choke.

Does the thin barrel prohibit the use of a sub-caliber sabot?