Introduction to Precision Shooting with Primary Arms SLx MicroPrism
On October 26, 2024, I attended a Long-Range Carbine Course hosted by The Gun Run at Dewitt’s Sporting Clays in Ellerbe, North Carolina. This event, led by Ellis, the owner and lead trainer, was an exceptional opportunity for students to push the limits of their skills and equipment on realistic targets at practical ranges designed for modern sporting rifles. Among the optics tested, the Primary Arms SLx MicroPrism with ACSS Aurora Reticle stood out as a favorite, particularly in the 3x and 5x configurations.
Why the Primary Arms SLx MicroPrism Excels at Intermediate-Range
The Primary Arms SLx MicroPrism ACSS Aurora Reticle performed remarkably across multiple calibers, from 5.56mm to 7.62x39mm, making it an ideal optic for intermediate-range accuracy. The fixed power and ACSS Aurora Reticle build on the classic design of the Trijicon ACOG with modern updates that enhance its usability and precision. This reticle, primarily in a BDC (Bullet Drop Compensating) format rather than MOA or MIL, is purpose-built for shooters aiming to improve their shot placement and consistency.
The Importance of Choosing the Right Zero with a BDC Reticle
During the course, many students opted for a short-range or 100-yard zero, but I wanted to emphasize the importance of selecting an optimal sight-in distance to maximize the capabilities of the Primary Arms SLx MicroPrism BDC reticle. For those who have access to a longer range, zeroing at a distance beyond 100 yards, ideally at 200 yards, can greatly enhance accuracy at extended distances.
Setting Up for a 200-Yard Zero with the Primary Arms SLx MicroPrism
For our setup, a 200-yard zero worked well. Here’s why:
- Ammunition: We used 7.62×39 ammunition, which, while not match-grade, offered about 3 MOA accuracy.
- Rifle Precision: With a 10.5” barrel, our rifle provided roughly 2 MOA precision.
Combining these factors, we anticipated a spread of 5 MOA, equating to a 15.7-inch group at 300 yards—sufficient to maintain accuracy on human-sized targets. The end goal is to have realistic performance from the firearm / ammunition combo. The 7.62x39mm ammunition has been a lethal caliber for well over 60+ years and understanding its capabilities is what we want to maximize on.
Using the Hornady Ballistic App for Optimal Sight-In
To fine-tune this setup, I used the Hornady Ballistic App with the G1 BC data. I input essential measurements, including:
- Sight Height: 2.5 inches
- Ammunition Velocity: 2250 feet per second
- Barrel Length: 10.5 inches
After adjusting the app to provide inch-based drop data, it suggested an optimal short-range sight-in at 29 yards. Placing a target at this distance allowed us to use the inner chevron of the ACSS Aurora Reticle as our aiming point, producing clear, visible groupings for further fine-tuning at extended ranges.
Understanding Short-Range Sight-In Limitations
While a short-range sight-in (like 29 yards) is helpful, it does have limitations. For example, adjustments at such a close range are minor, and precise clicks can be challenging due to the bullet diameter and optic’s adjustment increments. Still, this short-range zero aligns the line of sight with the bullet trajectory, preparing us for accuracy at greater distances.
Testing at Distance: Confirming Precision with the Primary Arms SLx MicroPrism
After the initial short-range sight-in, we moved to 200 yards. Our first few groups landed low but still on steel, indicating we were close. By the third group, the BDC reticle and trajectory aligned perfectly. We confirmed accuracy by shooting at 100 and 300 yards, with the BDC tracking reliably across these distances.
Final Thoughts
The Primary Arms SLx MicroPrism ACSS Aurora Reticle proved to be an excellent choice for intermediate-range precision shooting. With a thoughtful setup and correct sight-in distance, this optic allows shooters to take full advantage of its BDC reticle, providing accuracy across a range of distances. Watch the video below to see this setup in action and master the art of precision with the Primary Arms SLx MicroPrism.