When I got my SLP the fiber optic cable front sight was broke. It was brand new so I called FNH and they connected me with Browning Firearms, and they sent me a new one but it was the wrong one. I didn't want to wait for them to send me the right one so I took the front fiber optic cable from a bb gun I had. I added a little wd40 to the cable to get it to go though the holes of the front sight then I a put a small drop of super glue then slightly melted the muzzle end of the cable with a lighter to keep it from fallen out later, but it was a tight fit. You most like don't have a fiberoptic on a old bb gun so I would sugguest calling Browning, but make sure they send you the right part. Good luck and good shooting.