Yes, the 03A3 was used, but by WWII a lot of armories had switched over to the M-1C or M-1D, which was an accurized version of the M-1A, with the C and D being exactly similar except for how the scope was mounted. All three of these rifles, the 03A3, M-1C, and M-1D were extremely accurate, and would pretty much whip the pants off of any factory rifle of today, including the BDL at 100yrds, not to mention 800yrds!!! They were very accurized for their time, and I'd venture to say that even still, they'd be incredibly accurate compared to MOST rifles, even accurized benchrest rifles. The 03A3 was noticeably more accurate than the semiauto M-1's, and I've watched an M-1D throw 3" groups at 600yrds, .5MOA!!!
So...where ya getting the 03A3???
Screw the 10 ring, keep them in the zero!!!