To be a sniper, you've got to back it up. It isn't the rifle, it's the man behind it.
has arguably the most kills as a sniper. 505 confirmed kills during the Winter War in Finland. He used a Model 28/30, a variant of the Mosin-Nagant. With iron sights.
On the other hand, Carlos Hathcock
reportedly used a Model 70 Winchester, and a scope-mounted Browning M2.
It's not the rifle, it's the man behind it.