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Serpent Arms 550LR (.45 caliber) Air Rifle Review / Adding a .45 Barrel Kit to the R2 Air Shotgun

23 August 2025 / 61 views / Airgun Channel

Serpent Arms 550LR (.45 caliber) Air Rifle Review / Adding a .45 Barrel Kit to the R2 Air Shotgun

Made in the USA, the Serpent Arms 550L is one of the most versatile air-powered platforms available, combining the function of a 28-gauge air shotgun with the ability to convert into a .45 caliber air rifle by simply swapping the barrel. In this review, we take an in-depth look at how the conversion works, the performance differences between shotgun and rifle mode, and test the accuracy and power. With the optional .45 caliber barrel kit, complete with its own handguard and valve-stem collar, the 550L quickly transforms into a powerful big bore air rifle capable of delivering serious power. Using NSA .452 caliber 196-grain slugs with a 4,100 psi air tank, the .45 caliber rifle is able to reach impressive velocities of 815 feet per second while maintaining consistent accuracy across multiple shots.

This video covers everything from the initial setup of the 550L as an air shotgun, to the full installation of the .45 caliber conversion kit, and then into detailed performance testing with real-world results. You’ll see how the system handles in both configurations, what kind of accuracy you can expect at various ranges, and I'll show you how the Serpent Arms 550L airgun offers both flexibility and innovation, in a single platform. If you’ve been curious about big bore air rifles or multi-purpose PCP systems, this review will give you the complete picture of how this unique airgun performs.

You can get your own Serpent Arms 550L Air Shgotgun or .45 caliber Air Rifle at Serpent Arms by clicking here: https://www.serpentarms.com/shop-1?page=2

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