Why can not I insert more than 253 records in mysql?

Hello friends I am trying to insert several records at the same time but when generating this script it only allows me to insert a maximum of 253, where I send by means of POST the amount of 500, which I can be doing wrong?

if(isset($_POST["id_ncf"]))
{
    $ncf_d="1";
    $ncf_h="500";

    for($i=$ncf_d;$i<$ncf_h;$i++) {             
        mysql_query( "INSERT INTO ncf_inst (id_ncf,ncf_desde,ncf_hasta) VALUES ('$id','$i','$ncf_h')", $link) or die(mysql_error());
        mysql_select_db($database);
    }
    header("Location: prueba.php");
}