FN America submitted its 509 pistol as the firm's entrant to become the next sidearm of the U.S. military—the Modular Handgun System (MHS), which resulted in the XM17 pistol. We all know how that worked out, with the SIG Sauer based upon (but not the same as) the P320 winning the contract. And those guns are starting to be issued to combat troops. Even though FN didn’t win the big contract, the shooting public notched a win with the availability of the 509 pistol, ably reviewed by American Rifleman’s Kelly Young. Beretta's entrant in the MHS trials, the APX, is also commercially available. 
But there were some specifications asked for by the Army in the MHS competition that have made their way into a new pistol made in Columbia, S.C., in particular, the ability to accept a suppressor and an extended magazine. That gun is the FN 509 Tactical.
The polymer-framed, striker-fired 509 Tactical comes with a cold-hammer-forged 4 1/2” barrel threaded at the muzzle (1/2x28) for mounting a suppressor, as well as elevated sights that will allow you to properly aim while a can is attached to the gun (more on this later). Interestingly, FN provides an O-ring on the inside of the knurled cap, so it won’t walk while shooting. 
But it’s the rear sight assembly that really sets the 509 Tactical apart. It has a replaceable FN Low Profile Optics Mounting System (LPOMS, how's that for an acronym?) that will, through a series of plates, allow the mounting of at least 10 different red dot optics. I had a look at the system, and it seems that just about any major red dot is going to fit on this gun.
The rear sight has protective ears that are actually grooved on the front surface. So even though the front surface is angled, there are grooves there so you can still use those protective side ears to rack the slide against a duty belt or hard object if necessary.
There’s also big news when it comes to the double-column, single-feed magazine. You can get it with a 17-round flush-fitting magazine, or you can insert an extended 24-round capacity magazine that protrudes from the bottom of the grip. That was one of the requirements of the Army MHS trial, and it has jumped to the civilian version. The gun comes with two standard 24 rounders and one 17 rounder. 
And, somewhat mocking of Henry Ford, you can get it in any color you want so long as it’s Flat Dark Earth. No mention of a black version has been forthcoming. The suggested retail price is $1,049. Not bad for an optics-ready pistol. I have long been a fan of the FN pistols made in South Carolina, with the FN-P in 9 mm still being one of my favorites. No doubt the 509 Tactical will call much deserved attention to the excellent handguns made right here in the United States. 
Additional Reading:
Tested: The FN 509 Pistol
The Keefe Report: Proven—The FN America 509 Pistol
NRA Gun of the Week: FN FNX .45 Tactical FDE Pistol
