As an “old guy,” the first ARs I ever owned and operated were the original, full-sized rifles with fixed stock, fiberglass handguards and 20-inch barrels. I’ve always favored the original AR-15/M16A1 rifles of the Vietnam era that I grew up in. The rifles are complete with triangular handguards and shorter A1 buttstocks. In the post-Vietnam era, Colt’s M16 was improved over time through a series of variants from the original M16 through the A1, A2, A3 and culminating in the current A4 heavy barrel version. Those changes were added to the commercial Colt AR-15 sold to the general public and civilian law enforcement.

Colt’s AR-15A4 Rifle Is the Real Deal

Although there are a number of manufacturers producing full-sized AR-15A4 rifles, I consider Colt’s version to be the real deal due to its historical lineage. The A4 appeared before the now wholesale switch to the M4 carbine by the military and the vast majority of civilian and law enforcement AR-15 users. The full-sized A4 rifle still has a lot of life left in it.

The A4 rifle has several advantages over the M4 carbines. First, its 20-inch barrel length allows the 5.56mm cartridge to develop its full 3,200 feet per second maximum velocity. This also maximizes its effective range. With a 16-inch M4 carbine barrel, the 5.56 runs out of gas sooner. Though not a problem with the 16-inch-barreled XM177 used during the close-in jungle warfare of Vietnam, it was an issue for the wide-open desert warfare of the past 20 years.

Second, the full-length barrel also means a full-length gas tube. The 20-inch AR-15 rifles are smoother shooting than AR carbines or pistols because of a less-abrupt, better operational timing cycle. The difference in firing 16-inch carbines and 20-inch rifles is definitely noticeable.

The third advantage is increased sight radius for iron-sighted A4 rifles. If an AR-4 rifle is going to be kept stock for use as an all-around utility rifle, survival gun or competitive military match rifle — iron sights work best for these purposes — it will have the sighting advantage over an iron-sighted M4.

Colt AR-15A4 Specifications

  • Caliber: 5.56x45mm NATO
  • Capacity: 30+1, with included Magpul polymer magazine.
  • Barrel: 20-inch chrome-lined barrel, with A4 muzzle compensator and bayonet lug A2 handguards, front and rear sling swivels
  • Overall Length: 39.5 inches
  • Weight: 7.71 pounds
  • Upper and Lower Receiver Material: 7075 T6 aluminum, black hard-coat anodized
  • Barrel Material: 4150 CMV, manganese-phosphate coated
  • Barrel Twist Rate: 1:7 inches RH-6 grooves
  • Front Sight: A2 fixed
  • Rear Sight: Detachable carry handle — Picatinny upper receiver available for optics mounting
  • Trigger Type: Single-stage military ambidextrous fire control switches
  • Grip: Government Stock A2 with trap door for cleaning equipment (equipment not included)
  • Operating System: Direct gas impingement — full-length gas tube

The Colt AR-15A4 is more than a pound heavier than my Century Arms AR-15 A1, which makes it a bit more tiring to carry. However, it is also more accurate due to the stiffer barrel. The detachable carry handle lost some of the area for fingers due to needing to accommodate railing versus the original AR carry handle that has plenty of room. If you have large hands, the A4 handle won’t work well for carry. However, the A4 can still be grasped around the slip ring for carry like the A1.

Colt AR-15 at the Range

I took the Colt AR-15A4 out to the Briar Rabbit range for testing with just 20 rounds of Winchester 55-grain FMJ White Box Ammo. Even though the 1×7 barrel test rate is optimized for 62-grain ammo, 55-grain will still work decently enough.

I set up my B27 silhouette at 150 yards rather than 100 yards and used the 30-round mag as a field expedient rest. Yes, I know you aren’t supposed to do that. But I had forgotten my rifle rest.

I fired all 20 rounds in one string, and there were of course no malfunctions. The Colt AR-15A4 ran smoothly out of the box. But I found the iron sights were quite a bit off for me. Though I was holding on the orange center dot of the silhouette, the 20 rounds fired were situated low and to the left, with 17 rounds in the cardboard and three in the corner of the paper. This resulted in a 10-inch diameter group. Not bad for a rifle with a 6-pound, 15-ounce military trigger pull rested on the magazine base for steadiness at that distance. If I had been on the range by myself with more ammo, I would have adjusted the sights and gotten zeroed in.

Wrap Up

The Colt AR-15A4 is a great, traditional AR-15 rifle built by the first major military supplier and commercial manufacturer of a design that has been in use by our military for roughly 55 years. Even though the Colt AR-15A4 is no longer cataloged by Colt, it is still available in the commercial pipeline. I found one at Sportsman’s Outdoor Superstore for $1,099, and multiple rifles available at Vance Outdoors in Ohio for $1,199. It will supply you with years of service with minimal maintenance.


Sportsman’s Outdoor Superstore:
Vance Outdoors:

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