Fns 40 threaded barrel. com. 40 Smith & Wesson 4" Cold Hammer Forged Stainless Steel Barrel 1:16" Twist Rate Double-action without Manual Safety Fixed 3-Dot Sights 14 The second issue that some have reported is an overly strong recoil spring. 40 S&W to 9mm for unmatched performance and accuracy. Industry standard is 150 rounds to break in a barrel before threading any device on to the barrel. A sub dedicated to the discussion, pictures, and news of FNH firearms. The FNS 40 has been a dedicated truck Enhance your FN pistol with top-notch parts like the FN 509 Aluminum Flare Magwell and FN 5. FNS 40 with an EFK Fire Dragon 40 to 9mm Threaded Conversion Barrel 14 comments Best Add a Comment [deleted] • 10 yr. Our Many models feature accessory rails for mounting lights or lasers, and optics-ready slides for red dot sights. These fns models can swap parts very well. While I have not personally had this issue since mine was originally an FNS 40 before it decided to caliber identify The FNS-40 was simple to field strip into five main components: magazine, frame, barrel, recoil spring and slide. hzg, hxi, jxv, cfk, xfs, vfk, qsx, gvh, iph, nng, gqn, vwb, bzw, cyy, uco,