Get players on server near the player

[Isosceles]

I am trying to get a list of players to iterate through however

List<EntityPlayer> players = mc.theWorld.playerEntities; does not seem to be working once you leave chunks or those players leave chunks.

[Isosceles]

On the server (this will not work on the client):

FMLCommonHandler.instance().getMinecraftServerInstance().getPlayerList().getPlayerList()

Im sorry but I just noticed I worded it terribly, I meant I want a list of the loaded players entities on the players client.

[Isosceles]

It stops working once I move far away from my starting position, it tells me for example there is 12 players but if I relog it will show none.