I plan on dry roasting a beef chuck, I've only ever braised chuck before though. Is this cut suitable to a slow and low dry roast or will it come out tough? It's a 3 lbs roast, I'm thinking 300 degrees (convection) for and hour and 15 minutes.
Roasting is, by definition, "dry." Beef chuck can certainly be roasted, and your plan sounds reasonable. It can also be smoked, at an even lower temp. There are plenty of recipes online. Whichever your preference, I would measure temperature, rather than rely on time. I will also add, the texture will certainly be different from a braised chuck, if that is what you are used to.