My Beretta M689 9.3x74R o/u has the 61cm barrels with matching 20/76 ga barrels at 66cm. The rifle has a single trigger with a selector to always fire top barrel first. It has ejectors that are a must for o/u if you hope to reload quickly. Without them, it would be difficult to unload the lower barrel, or with the scope on. For scope, I use EAW mounts with a compact Leopold 30mm VariX-R 2-7x with illuminated red dot. I am very happy with this setup. It is easy to remove the scope to use the barrel sights and when I put it back on, it is always zeroed in the same place. It is a very balanced rifle with the Bavarian butt stock, and what I like about that stock is when I put the 20 ga barrels on, it still fits perfectly. That stock design also seems to work with the scope on or off as a rifle. I don't think you could do that with an American or English cut stock. I use a 14 3/4" length of pull, which seems to fit me very well. Game wise, I would not hesitate to use it on anything up to buffalo sized animals with good premium rounds. I'm sure it will (and has) taken game cleanly all the way up to elephant, but for that I think that I would use something bigger. Range wise, the 9.3x74R is a solid 200m round with the 286 gr RN load and 250m with one of the faster 232-250 gr loads. My rifle doesn't seem to be too picky with regulating different loads, but I have heard of other people who have had trouble. Only way to know is to just try and see.