The Walther Colt M4 OPS .22 LR is a dedicated survival gun chambered in the ubiquitous rimfire cartridge. Its function and accuracy excel over ordinary .22 conversion kits.
- Made by Walther, this Colt-licensed .22 is remarkably well built.
- A dedicated .22 AR-style rifle has advantages over a .22 conversion kit.
- The Walther Colt M4 OPS exudes detail and authenticity, making it a dandy trainer.
- The rifle sports a match-grade barrel and exhibited excellent accuracy.
Walther Colt M4 OPS
The advantage of conversion kits for your standard AR is that they are cheap and essentially give you two guns. However, the rifling on the AR is not standard for the .22 LR nor is the sizing of the barrel exact. The kits work, but many people prefer a dedicated AR-style rifle exclusively chambered in .22 LR, which improves the rifle’s function and accuracy.
Among ARs, the most popular are the carbine versions, and if you want a real M4, you must get a Colt. The problem is that Colt only sells the M4 to the military and law enforcement, and they don’t make one in .22. Colt does make other AR carbines for the civilian market but not in .22. Fortunately, Walther Arms has a fully licensed Colt M4 replica in .22 LR.
Walther Arms is a renowned German firearms manufacturer with more than 125 years of history and a solid reputation for quality and innovation. The company produces several licensed versions of famous firearms that they dub Tactical Rimfire Replicas. These full-sized replicas are made in Germany and come with all the details, weight, and handling characteristics of the originals.
The Walther-made Colt M4 OPS tactical AR carbine is a blowback-operated semi-automatic and is designed to be as close in appearance to the full-auto carbine currently issued to the U.S. Special Forces. The controls function just like on the original, which makes this an excellent rifle to use as a low-cost trainer.
Features and Innards
The Colt M4 OPS looks very authentic on the outside, but it’s a completely different animal on the inside. The rifle comes with a 16-inch steel match-grade barrel that is located inside the Parkerized metal barrel sleeve that replicates the contours of an M4 barrel. The barrel is topped off with an A1-style flash hider that is one of the few steel components in the rifle.
The front sight is a standard A2 gas block, and it is properly “F” marked for a carbine. It includes the bayonet lug and the front sling swivel. Carbines have a slightly different elevation of the front sight than rifles and should be F-marked. The front sight is adjustable for elevation as well.
One thing that distinguished the M4 OPS rifle from the other Colt AR replicas that Walther offers is the free-floated quad rail handguard. This handguard offers 6 inches of Picatinny rail space at the 12, 3, 6 and 9 o’clock positions and features Knight’s Armament-style one-piece polymer-ribbed rail panels for improved comfort while handling. They come off easily with a simple spring steel push lever and allow for the easy addition of any desired accessories such as lights, lasers, bipods, or forward vertical grips.
The upper and lower receivers are both made from aluminum like the original. The left side of the lower receiver carries all the proper markings with the Colt rampant horse logo and is labeled “M4 Carbine” above the serial number. It is marked “Hartford, Conn. USA” as appropriate. It does differ in listing the caliber designation as .22 LR. The real manufacturing information from Walther is on the right side of the lower receiver.
Getting the Details Right
I was impressed with the attention to detail in this replica. The trigger guard has the detent tab and hinges down for use with mittens or gloves, as the original. The upper and lower receivers look and feel just like on a real AR. The magazine release button works the same way, and the safety selector rotates 90 degrees from safe to fire (there is no full-auto marking, however) with the same resounding click and feel as the original.
The bolt release/hold is a separate piece and, rather than simply molded on, it is made from polymer instead of metal and is not functional. There is a steel forward assist that looks and feels real and moves as designed, but it too is for looks only. The dust cover is made of steel but remains fully functional, although the latch itself is polymer.
The metal charging handle has a functional latch and retracts to load and operate the rifle, but only about one-third of the distance as on an actual .223-chambered AR.
The furniture on the Colt M4 OPS is very accurate as well, with the polymer pistol grip and collapsible stock that includes a rear sling swivel. These did not seem quite as sturdy as on the real thing, but they don’t need to be. I also noticed that the adjustable length of pull on the stock provided five positions instead of six.
The upper receiver has a flattop design with Picatinny rail that forms a continuous length with the quad rail handguards. This provides 13 inches of uninterrupted space on which to mount optics. An A2 removable rear sight is included, allowing for both windage and elevation adjustments and includes dual aperture peep sights with the larger opening for shorter distances and the smaller opening for distances greater than 200 meters. This may be slightly optimistic, given the rifle’s chambering.
Disassembly of the Colt M4 OPS starts off very similarly to a standard AR. The takedown pins at the front and rear are fully functional but not captive. I found them to be very stiff and used a punch and a few taps from a light hammer to remove them. At that point, the upper and lower receiver halves came apart easily, and the guts of the rifle were exposed. There is nothing AR-like about the internals here. You get all zinc metal alloy construction that is housed inside an aluminum cover.
Ammo Adjustable Regulation
At the rear of the zinc receiver, inside the false upper receiver and just below the charging handle, there is a screw that can be turned to tune the bolt speed to correspond with the types of ammunition being used.
For high-velocity ammunition, the bolt speed can be increased by turning the screw clockwise. For low velocity, the bolt speed can be slowed by turning the screw counterclockwise. This should only be done if the rifle is experiencing cycling problems with the ammunition you are using. I tested three different types of ammunition and found that the rifle functioned just fine and no adjustment was necessary.
Operation on the Colt M4 OPS is almost identical to the real thing. From a training perspective, this is close to ideal, as the manual of arms will not significantly change. The 30-round magazine loads easily with dual side tabs that help the process along by allowing the operator to lower the follower and drop the rounds in.
The bolt hold open device is internal and will only lock open on an empty magazine. This is not ideal, but not uncommon for rimfire rifles. Once a full magazine is inserted, simply retract and release the charging handle to chamber a round, flip the safety selector to the fire position, and squeeze the trigger.
Load Up On .22 LR Mags
There are 10- and 20-round magazines available, but most people will opt for the 30-round mag. These are solidly built and not at all flimsy, but I found it to be too long for comfortable prone or benchrest shooting. It is in fact 2.5 inches longer than a standard AR 30-round magazine. I believe that the 20-round mag would be more comfortable and look more authentic.
Also, the reader should be aware that most dedicated .22 ARs use proprietary magazines, and they don’t often interchange between manufacturers. If purchasing aftermarket .22 AR magazines, check with the manufacturer beforehand to ensure proper fit and functioning.
The single-stage trigger had a fair amount of creep and a mushy yet heavy feel at the same time. I measured it at 8 pounds and found it to be a challenge in precision shooting. However, bad triggers are very common in real ARs and a creepy, mushy, heavy trigger is entirely Mil-Spec. Of course, with a standard AR, you can change the trigger, but not here.
How It Performed
The rifle weighed 6 pounds, 3 ounces when empty, which places it very close to a real AR carbine. It was sized and weighted properly, and the extensive use of metal and aluminum gave it a very real feel. It was light and easy to handle on the range, and I experienced no malfunctions firing offhand or from the bench.
Given the rifle’s tactical design, I opted for a red-dot sight with no magnification for accuracy testing at 50 yards from an improvised benchrest position. I say ‘improvised’ because the length of the magazine necessitated it. I mounted a Bushnell TRS-25 HiRise red-dot sight, which fit perfectly and features a 3 MOA dot. The 11 brightness settings make the dot visible in all light conditions and helped wring out the rifle’s accuracy potential.
Buyers of ARs chambered in .22 LR have a lot of options. You can buy a conversion kit that replaces the bolt carrier, or you can purchase a dedicated .22 upper receiver for your standard AR lower.
But for many, there is nothing better than an entirely dedicated rimfire AR rifle, and if you want one that looks and feels as close to the real thing as possible, you are only going to get it from Walther Arms. The licensed Colt M4 OPS is an accurate rifle that pays homage to America’s Special Forces and provides you with cheap, fun, and reliable operation.
Walther Colt M4 OPS
CALIBER: .22 LR
BARREL: 16.1-in. match
OA LENGTH: 31.1 in. collapsed, 34.4 in. extended
WEIGHT: 6.2 lbs. empty
SIGHTS: Adjustable iron sights
ACTION: Semi-auto blowback
CAPACITY: 30, 20, 10 rounds
Editor’s Note: This excerpt is from Modern Survival Guns: The Complete Preppers' Guide to Dealing with Everyday Threats, available now at GunDigestStore.com.