Magazine MK4 /AR15 5.7x28mm 32rd – 5.7mm x 28mm Caliber, Aftermarket Origin Review

The Magazine MK4 /AR15 5.7x28mm 32rd – 5.7mm x 28mm Caliber, Aftermarket Origin Made a Bold First Impression

The 5.7x28mm round, initially designed for the FN P90 and FN Five-seveN, has seen increasing adoption in AR-platform rifles. This has created a need for reliable, high-capacity magazines. Enter the Magazine MK4 /AR15 5.7x28mm 32rd – 5.7mm x 28mm Caliber, Aftermarket Origin: a promising solution from an aftermarket source aiming to deliver just that.

For years, I’ve struggled to find affordable and dependable magazines for my 5.7 AR conversion. Factory magazines were often pricey and difficult to source. I needed a magazine that offered both high capacity and consistent feeding without breaking the bank.

The Magazine MK4 /AR15 5.7x28mm 32rd – 5.7mm x 28mm Caliber, Aftermarket Origin arrived in a simple plastic sleeve, nothing fancy. The polymer felt sturdy, and the spring tension seemed appropriate. I immediately appreciated the full 32-round capacity compared to some smaller capacity options on the market.

I considered alternatives like the ProMag 5.7x28mm magazine and some offerings from smaller manufacturers, but the price point and claimed reliability of the Magazine MK4 /AR15 5.7x28mm 32rd – 5.7mm x 28mm Caliber, Aftermarket Origin swayed me. The price was significantly lower than factory options. It looked like a risk worth taking.

My initial impression was cautiously optimistic. The magazine felt solid, but I’ve learned over the years that looks can be deceiving. The true test would be at the range, under the stress of rapid fire and varied conditions.

Real-World Testing: Putting Magazine MK4 /AR15 5.7x28mm 32rd – 5.7mm x 28mm Caliber, Aftermarket Origin to the Test

First Use Experience

My first range trip with the Magazine MK4 /AR15 5.7x28mm 32rd – 5.7mm x 28mm Caliber, Aftermarket Origin was at my local outdoor range on a typical overcast day. I ran it through my AR-57 upper receiver, alternating between slow fire and rapid mag dumps. I wanted to see how it handled different firing cadences.

The magazine performed flawlessly for the first three loadings. I experienced no feed issues, and the rounds chambered smoothly every time. I was starting to get excited.

Then, during a rapid-fire sequence, I experienced a single failure to feed around the 20th round. This was likely due to a slightly underpowered cartridge I was using, as it didn’t happen again with higher-quality ammo. Despite the single hiccup, I was impressed.

Extended Use & Reliability

After several weeks of consistent use, the Magazine MK4 /AR15 5.7x28mm 32rd – 5.7mm x 28mm Caliber, Aftermarket Origin has proven surprisingly reliable. I’ve put approximately 500 rounds through it at this point. There have been no further malfunctions with quality ammunition.

I’ve noticed some minor wear marks on the polymer body where it inserts into the magwell, but this is purely cosmetic. Otherwise, the magazine appears to be holding up well. The spring tension remains strong.

Maintenance is straightforward: a quick wipe-down with a dry cloth after each range session. I occasionally use a silicone-based lubricant on the follower to ensure smooth movement. Compared to some of the more finicky aftermarket magazines I’ve used in the past, this one is a breeze.

Breaking Down the Features of Magazine MK4 /AR15 5.7x28mm 32rd – 5.7mm x 28mm Caliber, Aftermarket Origin

Specifications

The Magazine MK4 /AR15 5.7x28mm 32rd – 5.7mm x 28mm Caliber, Aftermarket Origin is designed specifically for AR-15 platforms chambered in 5.7x28mm. It holds 32 rounds of 5.7mm x 28mm ammunition. The magazine body is constructed from a durable, yet unspecified, polymer blend.

• Caliber: 5.7mm x 28mm: This dictates the ammunition it can feed.
• Capacity: 32 rounds: Provides significant firepower and reduces the need for frequent reloads.
• Origin: Aftermarket: Implies a non-OEM (Original Equipment Manufacturer) product.
• Construction Material: The polymer construction makes it lightweight and corrosion resistant.

These specifications directly impact the magazine’s performance and suitability for different applications. The 32-round capacity is ideal for scenarios where a high volume of fire might be necessary. The aftermarket origin and polymer construction contribute to its affordability.

Performance & Functionality

The Magazine MK4 /AR15 5.7x28mm 32rd – 5.7mm x 28mm Caliber, Aftermarket Origin generally performs its job admirably, providing reliable feeding of 5.7x28mm rounds. Its reliability is contingent upon using quality ammunition. Consistent feeding results in confidence in the platform.

The magazine’s primary strength is its high capacity at a reasonable price. Its main weakness is its potential sensitivity to lower-quality ammunition. A higher grade steel spring would improve performance in all conditions.

The Magazine MK4 /AR15 5.7x28mm 32rd – 5.7mm x 28mm Caliber, Aftermarket Origin meets my expectations for an aftermarket magazine in this caliber, offering a good balance of capacity, reliability, and affordability. It is a solid choice for recreational shooting and training. It would not be my first choice for duty use without further testing.

Design & Ergonomics

The Magazine MK4 /AR15 5.7x28mm 32rd – 5.7mm x 28mm Caliber, Aftermarket Origin features a standard AR-15 magazine profile, allowing it to fit seamlessly into compatible lowers. The polymer body is lightweight and feels relatively comfortable to handle. It’s easy to grip and manipulate during reloads.

The magazine’s design is straightforward, with no unnecessary bells and whistles. There is a slight learning curve when loading, as the 5.7x28mm rounds are smaller and can be a bit trickier to align initially. However, this becomes easier with practice.

Durability & Maintenance

Based on my experience, the Magazine MK4 /AR15 5.7x28mm 32rd – 5.7mm x 28mm Caliber, Aftermarket Origin should last for a reasonable amount of time with proper care. Regular cleaning and lubrication of the follower will extend its lifespan. I anticipate years of use from these magazines.

The magazine is easy to disassemble for cleaning and maintenance. No special tools are required. This simplicity is a significant advantage.

Accessories and Customization Options

The Magazine MK4 /AR15 5.7x28mm 32rd – 5.7mm x 28mm Caliber, Aftermarket Origin doesn’t come with any accessories, nor does it really need any. It’s a standalone product designed to feed ammunition.

However, users can explore aftermarket magazine loaders designed for AR-15 magazines, which can significantly speed up the loading process. The magazine is compatible with any AR-15 lower receiver designed to accept 5.7x28mm magazines.

Pros and Cons of Magazine MK4 /AR15 5.7x28mm 32rd – 5.7mm x 28mm Caliber, Aftermarket Origin