Don't know about accuracy. My concern is with accelerated wear on the chamber and feed ramp on a semi-auto.
He is going to use factory ammo in this rifle. Sound like they would be fine for his purpose. Thanks, Barlow+1. The other factor is inspecting each casing before and after resizing for degradation and splits. My experiences are they don't last or hold up as well as brass, but while they do, they shoot just fine.
Alex