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Parker Mountain Machine

PMM Duty Compensator for FN 509

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5 model listings

  • FN 509 FullsizeManufacturer documentedRequires a THREADED BARREL in 1/2x28. Most of these pistols do not ship with one — check your barrel before buying. NOT compatible: 509 Edge Series, 509 Compact MRD w/ Compensator, 509 Fullsize MRD, non-509 pistols. PMM allows other 1/2x28 barrels but warns the fit varies — "will work with others that have the same threads. (Gap may vary)" — which is a maker stating plainly that same pitch does not mean same shoulder standoff. Shim-and-timing, no set screws. Ammo guidance: best with +P or NATO spec; avoid Blazer 115, WWB 115, Armscor 115, PMC 115, and all reloads.
  • FN 509 Compact MRDManufacturer documentedRequires a THREADED BARREL in 1/2x28. Most of these pistols do not ship with one — check your barrel before buying. NOT compatible: 509 Edge Series, 509 Compact MRD w/ Compensator, 509 Fullsize MRD, non-509 pistols. PMM allows other 1/2x28 barrels but warns the fit varies — "will work with others that have the same threads. (Gap may vary)" — which is a maker stating plainly that same pitch does not mean same shoulder standoff. Shim-and-timing, no set screws. Ammo guidance: best with +P or NATO spec; avoid Blazer 115, WWB 115, Armscor 115, PMC 115, and all reloads.
  • FN 509 Midsize MRDManufacturer documentedRequires a THREADED BARREL in 1/2x28. Most of these pistols do not ship with one — check your barrel before buying. NOT compatible: 509 Edge Series, 509 Compact MRD w/ Compensator, 509 Fullsize MRD, non-509 pistols. PMM allows other 1/2x28 barrels but warns the fit varies — "will work with others that have the same threads. (Gap may vary)" — which is a maker stating plainly that same pitch does not mean same shoulder standoff. Shim-and-timing, no set screws. Ammo guidance: best with +P or NATO spec; avoid Blazer 115, WWB 115, Armscor 115, PMC 115, and all reloads.
  • FN 509 Midsize TacticalManufacturer documentedRequires a THREADED BARREL in 1/2x28. Most of these pistols do not ship with one — check your barrel before buying. NOT compatible: 509 Edge Series, 509 Compact MRD w/ Compensator, 509 Fullsize MRD, non-509 pistols. PMM allows other 1/2x28 barrels but warns the fit varies — "will work with others that have the same threads. (Gap may vary)" — which is a maker stating plainly that same pitch does not mean same shoulder standoff. Shim-and-timing, no set screws. Ammo guidance: best with +P or NATO spec; avoid Blazer 115, WWB 115, Armscor 115, PMC 115, and all reloads.
  • FN 509 MidsizeManufacturer documentedRequires a THREADED BARREL in 1/2x28. Most of these pistols do not ship with one — check your barrel before buying. NOT compatible: 509 Edge Series, 509 Compact MRD w/ Compensator, 509 Fullsize MRD, non-509 pistols. PMM allows other 1/2x28 barrels but warns the fit varies — "will work with others that have the same threads. (Gap may vary)" — which is a maker stating plainly that same pitch does not mean same shoulder standoff. Shim-and-timing, no set screws. Ammo guidance: best with +P or NATO spec; avoid Blazer 115, WWB 115, Armscor 115, PMC 115, and all reloads.

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