Not really about effective range but i was at the range the other day with a guy that shot a 7 shot group at 200 yards under an inch with a battered looking 91/30, theoretically and under the right conditions he could atleast shoot MOA to 1000 yards.
That was the only group i saw him shoot but he said that he never shoots over .75 MOA at 100 yrds. People underestimate the 54r because most of the time people are running crappy mil surp out of old warn out pitted barrels. They used these rifles and calibers for along time for a reason.
Just my opinion, feel free to flame me