Pure metal microspecimens have been found to exhibit strong size dependence of strength, but alloyed counterparts with a much refined microstructural length scale due to the precipitates present are as yet unknown. Here, compression tests on duralumin (aluminum 2025 alloy) micropillars reveal a much weaker size dependence of strength compared to pure Al, indicating the predominance of the internal length scale in determining strength. Creep is also significant in duralumin, probably due to the viscous overcoming of obstacles during deformation.