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Built for Duty: FN Military Collector Series M4 and M16
Many manufacturers of AR-style rifles for the commercial market say their product is built to military specifications, or Mil-Spec. But if they are intended for the commercial market, they are not truly Mil-Spec. They can’t be because Mil-Spec ARs are by definition select-fire guns that fire in either the semi-automatic or automatic mode. Some select fire models have a mechanism to limit the number of rounds fired with one pull of the trigger, and others are limited by only the number of rounds left in the magazine. Nevertheless, a commercial AR must be semi-automatic only.
But there is more to Mil-Spec than the fire control system, and even though many manufacturers recognize this fact and promote their guns as Mil-Spec, they may not be. For example, the Mil-Spec sets forth not only dimensions of parts and the materials used to make them, but also the testing procedure for assuring the part meets a minimum quality standard. In the case of the M4 or M16, each bolt must be built to those specifications, but also tested with a high-pressure round and then examined using a magnetic device to detect any flaws. Although some manufacturers may perform this test, some may not, and others may perform it on only a portion of the guns coming off the assembly line.
In the minds of most people, Mil-Spec denotes a very rugged, well made piece of equipment that will stand up to hard use in adverse conditions. And for this reason, as well as the fact that the M4 and M16 are well known to most people through movies and television, a lot of people just want to own whatever it is that the military is using.
The Military Collector
Other buyers just want to have a copy in their collection of the AR that is actually used by the military. Now, except for a few features that by law are not possible to include on an M4 or M16 destined for the commercial market, FN America has made it possible to own a genuine Mil-Spec gun.
The FN 15 Military Collector Series M4 and M16 have similar corresponding parts like handguards, bolt carrier groups and receivers, but the FN guns have actually been built to Mil-Spec where possible. And Mil-Spec means that not only are the parts made to a certain dimension, but the surface treatment is of a certain thickness and hardness, fasteners are affixed a certain way and certain inspection steps have been performed. To do these things costs more money than a typical manufacturer is willing to spend on a commercial AR.
Mil-Specs
Often the gas key bolts on a commercial AR are not secured according to the Mil-Spec. They may not be staked at all, or staked in a less expensive manner than called for by the Mil-Spec. Mil-Spec staking is done to lessen the chance that those bolts holding the gas key to the bolt carrier will loosen under use, but it costs more to stake them correctly.
To reduce costs, some commercial manufacturers will not subject bolts and barrels to high-pressure testing, or they will test only a portion of each production run. But Mil-Spec calls for firing a very high-pressure round through each gun and then running a magnetic particle inspection to assure that there are no cracks or other defects present.
According to J.P. Reconnu, FN 15 Product Manager for FN America, LLC, “The FN 15 Military Collector M4 and M16 are as Mil-Spec as you can get without having to enlist.”
He went on to say that there are only four main differences between the FN 15 and the real deal.
To comply with current law, the first is that they are set up for semi-automatic fire only. However, for authenticity of appearance, the markings on the receiver indicate safe, fire and auto. The second difference is, again to comply with current law, the 14.5-inch M4 barrel has a permanently attached flash suppressor making the barrel length 16 inches, whereas the real M4 has a removable flash suppressor. Third, the lower receiver does not bear the imprint “Property of U.S. Government.”
The fourth difference concerns the Unique Identifier (UID) label. That’s the sticker on the right side of the lower receiver that contains some writing and a QR code. On a real M4 or M16, it is used to identify the manufacturer and contains a specific code for each government contractor. Instead, the QR code on the Military Collector guns links to the FN website.
Otherwise, these guns really are Mil-Spec.
Features
The M4 is a carbine-length AR-pattern gun based on the M16. Besides shortening the barrel to 14.5 inches—16 inches with the permanently attached A2-style flash suppressor—and replacing the handguard with a shorter one, the buttstock is replaced with a collapsible buttstock with six positions. A sling swivel is located on the left side of the barrel just below the front sight. Those are the most obvious differences between an M4 and an M16.
The barrel on the M16 is 20 inches long and does not have the grenade launcher cut like the M4 does. While both guns have a bayonet lug at the base of the front sight base, the M16 also has a sling swivel attached at the bottom just in front of the handguard.
Bores and chambers on both guns are chrome-lined and barrels phosphate-finished. The handguards are made by Knights Armament, the M4 being the M4RAS and the M16 being the M5RAS. They sport M1913 Picatinny rails on four sides and are supplied with rail adapter covers. Also provided are vertical foregrips made by Knight.
The upper receiver on both the M4 and M16 are of the flat top design; no longer is a carry handle standard. Attached to the rear of the upper receiver is the correct flip-up iron sight made by MaTech. It is adjustable for windage and elevation and is graduated for aimed fire at 100-yard intervals from 200 yards to 600 yards. The front sights are both A2-style posts.
Triggers are Mil-Spec all the way, so don’t expect a competition trigger. These are military two-stage triggers designed for hard use, not precision or competition. Still, with practice, they are quite manageable. The safety or selector switch is ambidextrous, and the pistol grip is standard.
The bolt carrier group is, again, Mil-Spec, which means the bolt is properly marked with HPT-MPI indicating it was high-pressure tested and magnetic particle inspected. It and the bolt carrier are phosphate-finished, and the carrier is chrome lined.
In testing, the sample guns performed as expected. There were no problems encountered, and accuracy was actually better than is called for in the Mil-Spec.
If you are looking for the confidence inspired by owning a Mil-Spec AR, or if you just want the closest example a civilian can get on the commercial market to a real M4 or M16, FN has what you are looking for.
For more information, contact FN America, 855-536-4872, FNAmerica.com.
FN 15 Military Collector Series M4
Type: Semi-auto, direct gas impingement
Caliber: 5.56x45mm
Barrel Length: 16 in., 1:7 twist
Overall Length: 30.5 to 34.2 in.
Weight: 6.6 lbs.
Stock: Synthetic
Sights: A-2 style front, adjustable rear
Finish: Black phosphate and anodized
Capacity: 30+1 rounds
Price: $1,749
Performance:
FN 15 Military Collector Series M4
Load:
Black Hills 75-gr. Match BTHP
Velocity (fps):
2,710
Average Group (in.):
2.23
Best Group (in.):
1.69
Load:
Gorilla 77-gr. Sierra Matchking HP
Velocity (fps):
2,448
Average Group (in.):
1.08
Best Group (in.):
0.54
Load:
Speer Lawman 55-gr. FMJ
Velocity (fps):
3,116
Average Group (in.):
2.31
Best Group (in.):
1.74
FN 15 Military Collector Series M16
Type: Semi-auto, direct gas impingement
Caliber: 5.56x45mm
Barrel Length: 20 in., 1:7 twist
Overall Length: 39.5 in.
Weight: 8.2 lbs.
Stock: Synthetic
Sights: A-2 style front, adjustable rear
Finish: Black phosphate and anodized
Capacity: 30+1 rounds
Price: $1,749
Performance:
FN 15 Military Collector Series M16
Load:
Black Hills 75-gr. Match BTHP
Velocity (fps):
2,731
Average Group (in.):
2.82
Best Group (in.):
2.79
Load:
Gorilla 77-gr. Sierra Matchking HP
Velocity (fps):
2,531
Average Group (in.):
1.50
Best Group (in.):
1.41
Load:
Speer Lawman 55-gr. FMJ
Velocity (fps):
3,229
Average Group (in.):
3.43
Best Group (in.):
2.70
Editor's Note: This article is an excerpt from the July 2016 issue of Gun Digest the Magazine.
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