On arrival at Fanning River the pilot lowered the landing gear and obtained an indication that the landing gear was locked down. The aircraft subsequently touched down on the mainwheels and shortly after the pilot lowered the nosewheel to the ground, the nosegear collapsed. The aircraft slid to a stop on the strip, in a nosedown attitude. An inspection of the aircraft revealed that the nosegear assembly showed signs of excessive freeplay. This resulted in an excessive load on the downlock bracket and its ultimate failure in overload during this landing. The strip surface was rough, consisting of sandy soil covered with tufts of grass. The nature of the surface probably contributed to the failure.