Primary Arms SLx 1-6×24 Gen IV: A Montana Guide’s Honest Field Test

Three weeks into last November’s elk season, with snow falling sideways in the Absaroka Range, my hunting partner’s expensive European glass fogged up completely. Meanwhile, my Primary Arms SLx 1-6×24 kept trucking along like it had something to prove. That moment reminded me why I’ve been running this particular piece of glass on my .308 Winchester build for the past eighteen months – sometimes the underdog surprises you.

Listen, I’ve looked through more scopes than I can count during my eight years as an Army Ranger and another decade guiding hunters through Montana’s backcountry. From budget Chinese glass that wouldn’t hold zero if you sneezed near it to tactical optics that cost more than most folks’ mortgage payments. The Primary Arms SLx 1-6×24 Gen IV sits in that sweet spot where performance meets practicality, and after putting thousands of rounds downrange with this thing mounted up, I’m ready to share what I’ve learned.

Why Listen to a Crusty Montana Guide?

Before we dive into the meat and potatoes, let me establish why you might want to hear what this weathered mountain dweller has to say. I’ve been teaching survival skills and guiding hunters since before tactical scopes became the norm. My grandfather taught me to shoot iron sights on his Winchester Model 70, and I learned the value of quality optics the hard way – through broken equipment, missed opportunities, and lessons written in mud and snow.

These days, when I’m not teaching wilderness survival courses or volunteering with our local search and rescue team, I’m testing gear in conditions that would make most product reviewers pack up and head home. The Bitterroot Mountains don’t care about your warranty card, and neither do I. If gear can’t handle what Montana throws at it, it doesn’t belong in my kit.

Breaking Down the Primary Arms SLx 1-6×24 Gen IV

Technical Specifications That Actually Matter

Here’s what you’re working with when you mount this scope:

Core Specs:

• Magnification Range: 1-6x (actual magnification, not marketing fluff)
• Objective Diameter: 24mm
• Eye Relief: 4 inches (consistent across power range)
• Field of View: 120 feet at 1x to 20 feet at 6x (at 100 yards)
• Weight: 17.9 ounces (about the same as a loaded 20-round magazine)
• Overall Length: 10.4 inches
• Illumination System: Red center dot, 11 brightness levels
• Adjustment Value: 0.1 MIL per click
• Construction: Single-piece 6063 aluminum tube

Now, numbers on paper are about as useful as a screen door on a submarine if they don’t translate to real performance. So let’s talk about what these specs mean when you’re belly-down in wet leaves, trying to make a clean shot on a whitetail at first light.

Real-World Testing: Beyond the Bench

The Torture Test Protocol

When I test optics, they go through what my wife Sarah calls “The Flint Treatment.” Here’s what this Primary Arms scope endured over eighteen months:

Environmental Testing: I mounted this glass on my custom .308 build (Remington 700 action in an MDT chassis) and carried it through every season Montana could throw at us. From -15°F mornings checking trap lines to 95°F afternoon varmint hunts, this scope experienced temperature swings that would make lesser optics cry uncle.

Remember, the wilderness doesn’t care about your schedule – or your equipment’s comfort zone. During a particularly nasty December storm near Glacier National Park, ice formed an inch thick on everything exposed. The SLx’s turret caps kept the adjustments protected, and once I knocked the ice off, the glass was still crystal clear. No internal fogging, no frozen adjustments.

Impact Testing: Look, I don’t intentionally abuse gear, but sometimes Scout (my German Shorthaired Pointer) gets excited and knocks things over. During a coyote hunt last February, my rifle took a tumble off the tailgate – about a four-foot drop onto frozen ground. My grandfather would’ve skinned me alive for that kind of carelessness, but it gave me valuable data.

After checking for damage and finding none, I put five rounds of Federal Gold Medal Match 168-grain through paper at 100 yards. The group measured 1.1 MOA, same as before the fall. Zero hadn’t shifted a hair. That’s when this scope earned a permanent spot in my gear rotation.

Glass Quality: What You See Is What You Get

The optical clarity surprised me, especially considering the price point. At dawn and dusk – what we call the magic hours for hunting – the glass gathers light effectively. Is it Swarovski quality? No, and if you expected that at this price, you need to adjust your reality settings.

What you get is serviceable, clear glass that’s more than adequate for shots out to 400 yards in decent light. There’s some chromatic aberration at the edges when you’re at 6x, particularly noticeable against snow or sky. But here’s the thing – you’re not taking pictures for National Geographic. You’re putting rounds on target, and for that purpose, this glass performs admirably.

During a spring black bear hunt with my son, we spotted a decent boar at 275 yards through thick timber. The 6x magnification gave us enough detail to judge the bear properly, and the ACSS reticle’s BDC marks made the hold dead simple. One shot, clean kill, meat in the freezer.

The ACSS Reticle: Complexity Made Simple

Primary Arms’ ACSS (Advanced Combined Sighting System) reticle might look busier than a one-legged cat in a sandbox at first glance, but once you understand it, everything clicks. The chevron center provides a precise aiming point without obscuring your target like traditional crosshairs might.

The BDC (Bullet Drop Compensator) portion works surprisingly well with common .308 and 5.56 loads. I’ve verified the holds out to 600 yards with my .308 shooting 168-grain match ammo, and they’re close enough for government work. Wind holds are built in too, though I still prefer to dial or hold based on actual conditions rather than trust generic marks.

What sets this reticle apart is its versatility. At 1x with illumination cranked up, it functions like a red dot for close work. Zoom to 6x, and you’ve got ranging capabilities and holdover points for longer shots. It’s like having multiple sighting systems in one package.

Eye Relief and Eye Box: Room to Work

That four-inch eye relief is consistent whether you’re at 1x or 6x, which isn’t always the case with variable optics. I learned to appreciate this during a tense moment last season when a bull elk appeared at 40 yards while I was glassing distant ridges at 6x.

The generous eye box meant I could acquire the target quickly despite being in an awkward seated position against a deadfall. Lesser scopes would’ve given me a nice view of black scope shadow while that bull walked away. Instead, I filled the freezer.

Illumination System: Bright Ideas

The 11 illumination settings range from “barely visible in complete darkness” to “full noon sun bright.” The daylight-visible settings actually work – something that can’t be said for many scopes in this price range.

During a predator hunt last March, I called in a coyote just as the sun broke the horizon. The backlighting would’ve made the black reticle disappear, but cranking the illumination to setting 9 made the center dot pop like a road flare. That dog didn’t know what hit him.

Battery life has been solid. I’m still on the original CR2032 after eighteen months, though I keep spares in my pack. Practice makes permanent, so practice changing batteries in the dark with cold fingers before you need to.

Tracking and Adjustments: Do They Work?

The turrets provide positive, tactile clicks at 0.1 MIL increments. After running a proper box test at 100 yards, tracking proved true with perfect return to zero. I’ve dialed this scope for distance shots numerous times, and it always comes back home.

The capped turrets protect against accidental adjustment – crucial when bushwhacking through thick timber. I’ve seen too many hunters miss because their exposed turrets got spun without them knowing. These caps aren’t fancy, but they work.

Durability: Built Montana Tough

Beyond my accidental drop test, this scope has endured:

• Temperatures from -15°F to 95°F
• Complete submersion during a river crossing mishap
• Three months of daily use during hunting season
• Approximately 3,000 rounds fired
• More truck vibration than a paint mixer

The anodized finish shows minimal wear despite regular use. The integrated throw lever (a nice touch at this price point) still operates smoothly, allowing rapid magnification changes even with gloved hands.

The Competition: How It Stacks Up

Versus Vortex Strike Eagle 1-6×24

My buddy runs the Strike Eagle on his AR-15, and we’ve compared them extensively. The Strike Eagle costs about the same but falls short in several areas. The eye box is less forgiving, making rapid target acquisition more difficult. The illumination isn’t truly daylight bright – more like “cloudy day visible.”

The Strike Eagle’s simpler reticle might appeal to some, but I find it less versatile than the ACSS. Build quality feels comparable, though the Primary Arms has proven more consistent in holding zero through temperature changes.

Versus Swampfox Arrowhead 1-10×24

The Arrowhead costs roughly 40% more and offers greater magnification range. The true 1x (the Primary Arms is closer to 1.1x) and locking turrets are nice features. However, it’s noticeably heavier, and the extra magnification isn’t always useful in practical hunting scenarios.

Unless you specifically need 10x magnification, the Primary Arms offers better value. That price difference buys a lot of ammunition for practice, which matters more than gear in most cases.

Versus Trijicon AccuPoint 1-6×24

Now we’re talking about spending three times as much. The AccuPoint’s glass is noticeably superior – clearer, brighter, better color rendition. The fiber optic/tritium illumination never needs batteries, which appeals to my preparedness mindset.

But here’s the hard truth: for most shooters in most situations, the Primary Arms will get the job done just as well. Unless you’re law enforcement, military, or have money to burn, that extra $800 goes further spent on training courses or ammunition.

Practical Applications: Where It Shines

Hunting Applications

This scope excels for:

• Whitetail hunting from treestands to food plots
• Western spot-and-stalk within 400 yards
• Predator calling where shots range from 20 to 300 yards
• Black bear hunting over bait or spot-and-stalk
• Wild hog hunting where quick shots are common

Sarah, our household wildlife biologist, particularly appreciates how the 6x magnification allows for proper animal identification before shooting. Too many hunters make mistakes with inadequate optics.

Tactical and Defense Use

While I’m not kicking in doors anymore, this scope would serve well for:

• Home defense carbines (1x for inside, 6x for property surveillance)
• 3-gun competition where versatility matters
• Ranch rifles needing to handle varmints to predators
• Scout rifles requiring a do-everything optic

Training and Recreational Shooting

The clear tracking and reliable adjustments make this excellent for:

• Learning to shoot distance with holdovers
• Understanding MIL measurements and ranging
• Precision rifle training on a budget
• General marksmanship practice

Installation and Setup Tips

Mounting Considerations

Proper mounting makes or breaks a scope’s performance. Here’s my process:

1. Choose Quality Rings: Don’t put a $300 scope in $20 rings. Get something solid from Warne, Leupold, or similar. I prefer a one-piece cantilever mount for ARs.
   
2. Level Everything: Use a proper scope leveling kit. A canted reticle will drive you crazy and make the BDC useless.
   
3. Torque Properly: Follow manufacturer specifications. Too tight damages the scope; too loose means shifting zero.
   
4. Loctite Intelligently: Blue Loctite on ring screws and mount-to-rail screws. Never on adjustment turrets.
   

Initial Zero Process

Start at 25 yards to get on paper, then move to 100 yards for final zero. The ACSS reticle is designed for specific zeros depending on caliber – follow the manual here. Don’t try to reinvent the wheel.

Recommended Accessories

These additions enhance the setup:

• Throw Lever Extension: The included lever works, but aftermarket options provide better grip
• Lens Covers: Replace the basic caps with flip-ups for quicker deployment
• Anti-Reflection Device: Reduces signature and protects the objective lens
• Scope Coat: Neoprene cover for protection during transport

The Honest Limitations

No gear is perfect, and honest reviews acknowledge limitations:

What Could Be Better

Edge Distortion: At 6x, the outer 15% of the image shows noticeable distortion. Not a deal-breaker for center-hold shots, but it’s there.

True 1x: It’s closer to 1.1x magnification at the bottom end. Both-eyes-open shooting is still possible but takes adjustment.

Turret Feel: While functional, the turrets lack the crisp, definitive click of premium optics. They work, but they don’t inspire confidence like high-end glass.

Weight: At nearly 18 ounces, it’s not ultralight. Fine for standard rifles but noticeable on lightweight builds.

Who Should Look Elsewhere

This isn’t the scope for you if:

• You need true long-range capability beyond 600 yards
• You demand the absolute best glass quality
• Weight is your primary concern
• You’re outfitting a safe queen that’ll never see mud

The Bottom Line: Value Meets Performance

After eighteen months and thousands of rounds, the Primary Arms SLx 1-6×24 Gen IV has earned its place in my working rifle collection. It’s not perfect, but perfection is the enemy of good enough, and this scope is more than good enough for 90% of shooters in 90% of situations.

The combination of useful features, adequate glass quality, proven durability, and reasonable price makes this a winner for practical shooters. It bridges the gap between close-quarters and medium-range shooting better than any other scope I’ve tested at this price point.

Your best survival tool is the six inches between your ears, but having reliable equipment you can trust makes everything easier. This scope has proven itself reliable in conditions that would sideline prettier glass. It’s taken the knocks, handled the weather, and kept putting rounds where I aimed them.

Field FAQs: Real Questions, Honest Answers

Can this replace both iron sights and a traditional scope?

For most applications inside 400 yards, absolutely. I’ve run this as my only optic on several rifles with complete satisfaction. However, backup iron sights never hurt if your rifle accommodates them.

How’s the warranty and customer service?

Primary Arms offers a lifetime warranty, and they’ve honored it without hassle for other products I’ve purchased. That said, I haven’t needed to warranty this particular scope – it’s still running strong.

Will it handle magnum calibers?

I’ve seen these mounted on .300 Win Mags and .338 Lapuas without issues. The construction is robust enough for any reasonable sporting caliber. Just ensure your mount and rings are equally sturdy.

Is the illumination really daylight bright?

Yes, settings 9-11 are visible in bright sunlight. Not as blazing as some red dots, but absolutely usable for quick acquisition in any lighting condition I’ve encountered.

How does it perform in extremely cold weather?

Down to -15°F, I’ve had zero issues. The adjustments stay smooth, the glass doesn’t fog internally, and the battery keeps working. Colder than that? Can’t say – I’m tough, but not that tough anymore.

Final Thoughts: A Tool That Works

Every piece of gear in my kit needs to earn its place through proven performance, not marketing hype or brand reputation. The Primary Arms SLx 1-6×24 Gen IV has earned that place through consistent reliability in harsh conditions and practical accuracy when it counted.

Is it the best scope ever made? No. Is it the best scope most shooters can buy for under $400? I’d argue yes. It offers features and performance that would’ve cost four times as much a decade ago.

Remember, expensive gear doesn’t make you a better shooter – trigger time does. This scope gives you quality that won’t hold you back while leaving money in your pocket for ammunition and training. In my book, that’s a winning combination.

The wilderness doesn’t care about your equipment’s pedigree, only whether it works when you need it. After eighteen months of hard use, I can confidently say the Primary Arms SLx 1-6×24 Gen IV works. Whether you’re defending the homestead, filling the freezer, or just punching paper on weekends, this glass will serve you well.

Plan for the worst, hope for the best, and choose gear that won’t let you down when things get sporty. This scope fits that bill.

Stay sharp, stay ready, and remember – respect the game, respect the land, respect yourself.

Want to improve your marksmanship or learn more about choosing the right optic for your needs? Check out our other guides on Moosir.com where we break down everything from basic rifle skills to advanced hunting techniques. Because in the end, knowledge and practice matter more than any piece of gear you can buy.