FN rolled out its latest iteration in the FN 509 series, introducing consumers to the MRD Midsize model capable of supporting a red dot. FN does all the heavy lifting in terms of providing what you need to get started – shipping a handy package of mounts, screws and washers ready to pair with some of the most popular pistol red dots on the market.
Guns.com stopped by FN to get the deets from Pistol Product Manager Tom Victa on the best way to install an optic on the FN 509.
Steps to Install an Optic on the FN 509
1. Field Strip the FN
To kick off the mounting process, the FN is field stripped. As always, when disassembling any gun, the very first step is to make sure the gun is free and clear of any ammunition. From there, flip the take-down lever switch down, pull the trigger and rock the slide from the frame of the pistol.
2. Use Torx Wrench to Remove Screws on Cover Plate
Once the slide is free from the frame, grab the Torx Wrench from the tools package. Turning counterclockwise, remove both screws from the cover plate on top of the slide and set aside.
3. Use the Mounting Plate to Seat Optic in Place
FN’s instruction manual clearly labels which mounting plates work with which optics. Using that as a guide, grab the appropriate mounting plate from the tools package. Place the mount onto the slide, then seat the red dot on top of the mounting plate. Use the appropriate thread-locking screws to secure the red dot in place. FN’s mounting screws are thread-locking, therefore, no additional thread-locking materials are needed.
4. Reassemble the FN 509
Now that the optic is in place, it’s time to reassemble. Line the slide back up with the frame’s rail, rocking it back onto the frame. Once it’s seated, flip the take down lever up to secure the slide onto the frame and viola! You’re FN 509 is now ready to roll.