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Product Spotlight: Brownells BRN-601 Retro Upper Receiver

In this article, the focus is on the rediscovery and reimagining of the classic Colt Model 601 rifles in the form of the innovative Brownells BRN-601 Retro Upper Receiver Assembly. The said assembly is a modern, detail-accurate replica of the original Colt Model 601 rifles that were adopted by the U.S. Air Force back in 1962, marking an important milestone in the annals of the United States armed forces as the first AR-15/M16 platform rifle to enter service.

The appeal of the BRN-601 lies not only in its historic connections but also in its careful reconstruction using contemporary materials and manufacturing technology. Bearing a remarkable likeness to its predecessor, the BRN-601 is a fitting tribute to the original model while also incorporating improvements such as a more rugged reinforced injection-molded polymer replacing the brittle fiberglass of the original handguards. The article further outlines the various features and benefits this product has on offer.

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Origins of Brownells BRN-601 Retro Upper Receiver

Its historical background

The BRN-601 Retro Upper Receiver Assembly is a modern reinvention of a classic component of the original Colt manufactured rifles. This assembly is a contemporary remake of the Retro 601, which was the first Colt rifle manufactured between 1960 and 1962. The original Colt Model 601 was groundbreaking in its time, representing the first manifestation of the AR-15/M16 platform of rifles ever introduced into the United States armed forces. This monumental moment for the US military history saw the original Colt Model 601 rifles being embraced by the U.S. Air Force in 1962.

Influence on later models

The original design had a considerable influence on later models, providing the foundational basis upon which modern AR-15 and M16 platform rifles evolved. However, it is noteworthy that the BRN-601 has unique physical attributes that somewhat set it apart considerably from modern variants and later models of the M16 and AR-15 rifles.

Physical Design and Appearance

Description of physical design

The BRN-601 Retro Upper Receiver assembly has numerous features that emphasize the authenticity of the retro aspect. It boasts an early three-pronged duckbill flash hider that is firmly fixed with an original split-ring crush washer. The contour of the slim barrel mirrors that of the original, encasing a chrome-lined bore with a 1-12″ rifling, a distinct and unique feature of the initial design.

Comparison to modern and later models

Notwithstanding the glaring similarities, certain components make the BRN-601 Retro Upper Receiver assembly noticeably different from later and modern models of the AR-15 and M16 rifles. Unlike the more contemporary versions, the 601 lacks the forward assist feature and the pronounced shell deflectors.

Key Features of Brownells BRN-601 Retro Upper Receiver

A closer look at the ‘duckbill’ flash hider

The duckbill flash hider does more than just adding to the aesthetic value of The BRN-601. This three-pronged attribute, in collaboration with the correct original split-ring crush washer, is replicated accurately from the original Colt Model 601 rifles.

The importance of the original split-ring crush washer

One key characteristic of the early Colt Model 601 is the original split-ring crush washer. This feature in the BRN-601 helps to highlight the authentic replication of the classic piece, showcasing the meticulous structuring involved in its re-manufacture.

The uniqueness of the slim barrel

The slim barrel of the BRN-601 ensures a correct preservation of the original contour. The chrome-lined bore and the specific 1-12” rifling, unique characteristics from the original design, have been carefully maintained in this model.

Product Spotlight: Brownells BRN-601 Retro Upper Receiver

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Highlight on the Front Sight Post

Working in harmony with the A1 rear sight

The front sight post, though being non-F marked, is strategically designed at the correct height to facilitate cohesion with the A1 rear sight on the carry handle.

The lack of pronounced shell deflector

The BRN-601 Retro Upper Receiver features a lack of a pronounced shell deflector, an intentional move that supports the original design and differentiates it from the more modern models.

Handguard and Modern Reinvention

The enduring power of the green triangular handguard

The green triangular handguard is another feature that is designed to mimic the original Retro 601. While the first version consisted of a rather fragile fiberglass material, the BRN-601 has remodeled this attribute to be significantly distinct yet representative of the original design.

Replacing the fiberglass with modern reinforced injection-molded polymer

Adding a touch of modernity, the BRN-601 swaps the somewhat fragile fiberglass material that was used for handguard manufacturing in the original model, for a more durable and reinforced injection-molded polymer—one that captures the original contour but provides the durability expected of a modern rifle.

Delta Ring and its Originality

The slim profile of the Delta ring

Maintaining the ethos of the original model, the BRN-601 Retro Upper Receiver features the vintage, slim profile Delta ring. This aspect is notably absent in the modern A2 Delta ring, thus making it a distinguishing attribute.

The notable absence of the beefier modern A2 Delta

The Delta ring in the BRN-601 lacks the bulk or beefiness often associated with the modern A2 Delta. This is a deliberate move designed to keep users connected with the original vintage aesthetic associated with the Retro 601.

The Dust Cover

How it matches the contour of the original

In reinforcing nostalgia, the dust cover on The BRN-601 has been conscientiously designed to reflect the contour of the original model.

The general look and feel of the dust cover

The dust cover presents a distinct exploration into the original concept, capturing the detailed features and replicating it in a manner that appeals to both the modern and the classic rifle enthusiast’s eye.

Anodizing: Giving the Retro Look

The light grey anodizing on the receiver

Topping off the classical appeal of the BRN-601 is the visual characteristic of the receiver area. Impressively detailed, the receiver sports a light gray anodizing—a feature that resonates with the exact semblance of the original Model 601 rifles.

How it evokes the actual Model 601 rifles

The light grey anodizing is a subtle but powerful reminder of the historical relevance of the original Model 601 rifles, reinforcing the retro aesthetic in an impressively notable manner.

Behind the Carry Handle: The Rear Sight

Exploring the early A1 rear sight

Nestled in the rear of the carry handle is the early A1 rear sight, another iconic feature of the original design. This operates with the vertical adjustment wheel and is notably different from the A2 rear.

The difference from the A2 rear

Unlike the modern versions, BRN-601’s rear sight follows the design of the A1 instead of the A2. This decision contributes to the overall vintage aesthetic and ensures the consistency of the replica’s design fidelity to the original.

Its interaction with the ‘non-F’ front sight

Despite being non-F marked, the front sight post interacts seamlessly with the A1 rear sight, a factor that ensures optimal functionality while keeping true to the original design specifications.

Conclusion: Revisiting the Past with The Brownells BRN-601 Retro Upper Receiver

Why it is worth considering

If you’re a fan of classic designs given a modern-day touch, then the Brownells BRN-601 Retro Upper Receiver Assembly is a product worth considering. It merges the past’s aesthetics with modern-day technological advancements, providing you with reliable functionality without compromising the nostalgic allure that the original design offers.

How it keeps the spirit of the original model alive

The BRN-601 Retro Upper Receiver stands as an emblem of historical appreciation and pays homage to the original Colt Model 601 rifles. Its design and manufacturing intricacies project a keen adherence to the original model’s subtleties and peculiarities. Through this impeccably detailed reinvention, Brownells has not only revitalized the spirit of the original model but has succeeded in bringing a piece of historical relevance to the modern consumer’s reach.

See the Product Spotlight: Brownells BRN-601 Retro Upper Receiver in detail.