Many of you with L42's will find that this 'SCREW, securing, foresight' is now a standard 4BA allen bolt. We used to use allen bolts instead of the rubbish original screw simply because they were so useless. If the snipers or training staff didn't have the correct tool - which they didn't - then they'd just use any old pair of snipe nosed pliers or Leatherman tool which burred the screw up.