TFB Review: Leupold Mark 4HD 1-4.5X25 M5C3 SFP Scope + Torture Test

When it comes to optic durability, Leupold has always had a strong reputation, especially among professionals and law enforcement. The Leupold Mark 4HD 1-4.5X25 M5C3 SFP Scope is no exception. It's designed to serve those who require precision and durability in the field, and after spending some quality time with this scope, I can confidently say it lived up to my durability expectations.

This past March I reached out to Leupold and asked them to send me one of their cheaper optics as I wanted to really beat it up and see how it compared to another optic I was testing at the time. They were more than happy to send out the cheapest scope of their newer Mark 4 line and while I wouldn't say $1,000 is cheap, it's cheaper…

The Mark 4HD 1-4.5X25 M5C3 SFP Scope was sent to me by Leupold for this review and while I am allowed to keep this optic indefinitely, this will not change my current or future opinion on any Leupold products. I have been using this optic on two separate AR-15 rifles over the past few months on many trips to the range and near the end of its testing I also beat on it to see if it could hold zero and maintain its waterproofing.

More Leupold @ TFB:

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Specs - Mark 4HD 1-4.5X25

• Magnification: 1-4.5X
• Objective Lens Diameter: 25mm
• Tube Diameter: 30mm
• Field of View (FOV) at 100 yards:

• 1X: 74.0 feet
• 4.5X: 19.0 feet

• Eye Relief:

• 1X: 4.2 inches (107mm)
• 4.5X: 3.7 inches (94mm)

• Reticle: Second Focal Plane (SFP)
• Adjustment Click Value: 0.1 mil per click

• Parallax: Fixed, set at 150 yards

• Body Material: Aircraft-grade Aluminum
• Finish: Matte Black
• Waterproof, Fogproof, Shockproof: Yes (Leupold’s proprietary gas blend for sealing)

The Mark 4 1-4.5X25 feels solid in hand, which is reassuring, especially when you’re investing in a high-quality piece of equipment like this. Leupold has utilized aircraft-grade aluminum for the body, ensuring it’s both lightweight and durable. This scope comes in at 17.9 ounces (without mount) and 24 ounces with Leupold’s mount. The matte black finish is not just for aesthetics; it also helps reduce glare and the coating held up pretty good during my many drop tests.

Optical Performance - Mark 4HD 1-4.5X25

Optical clarity is one of the most critical aspects of any scope, and the Mark 4HD 1-4.5X25 does not disappoint even with its lower price. The glass is crystal clear, providing a sharp and bright image even in low-light conditions. The lenses are fully multi-coated, which enhances light transmission and reduces glare. This is particularly beneficial during dawn or dusk, when lighting conditions can be challenging with light being more likely to wash out the image.

The 1-4.5X magnification range is ideal for close to mid-range engagements.

At 1X, it’s perfect for quick target acquisition, almost like using a red dot sight. The 4.5X magnification provides enough power for more precise shots at medium distances. While it doesn’t offer the long-range capabilities of higher magnification scopes, the Mark 4 excels in its intended role as a versatile, close-quarters optic. One day I was able to connect pretty consistently at 400 yards on a man-sized steel target and nothing sounds better than that little ping.

Reticle and Adjustments - Mark 4HD 1-4.5X25

The Mark 4 features a Second Focal Plane (SFP) reticle, which means the reticle size remains constant as you change magnification. For a scope with a maximum magnification of 4.5X, this makes sense. The reticle stays easily visible and uncluttered, which is critical when you need to make quick adjustments in the heat of the moment. The Firedot in the center of the optic provides illumination when shooting into the evening. I’m happy to see its inclusion in this optic while it was missing from the  Mark 5HD 2-10 I tested last year.

The Firedot makes up close shooting easier as you can shoot with both eyes open just like on a standard Red Dot. I do wish the dot was brighter though as it was sometimes hard to see in the midday light. You can barely see it hovering over my head in the image to the top left. It's not visible in the picture to the top left because my camera was not focused on it.

The M5C3 turrets are definitely worth a mention and I'm pleasantly surprised to see them on the Mark 4HD series. They offer precise and repeatable adjustments, with tactile and audible clicks that are easy to feel and hear. Each click adjusts the point of impact by 0.1 mil, and the turrets are designed to return to zero without any hassle. One of the standout features of the M5C3 turrets is the ZeroLock system, which prevents unintentional adjustments. This system is particularly useful in high-stress situations where accidental changes could mean the difference between hitting or missing your target.

Durability and Testing - Mark 4HD 1-4.5X25

Leupold optics aren’t cheap, and the Mark 4 is no exception. Even at $1,000 this is an expensive optic. However, you do get what you pay for. The build quality, optical clarity, and reliability make this scope a solid investment for those who need a dependable optic for tactical or professional use. While it might be overkill for casual shooting or hunting, it’s an excellent choice for those who want a rugged optic they don't have to baby.

Final Thoughts - Mark 4HD 1-4.5X25

After spending time with the Leupold Mark 4 1-4.5X25 M5C3 SFP Scope, it’s clear that this optic is designed with professionals in mind. It’s tough, reliable, and offers excellent optical performance, all in a compact package. While the price tag might be steep for some, the quality and durability you’re getting make it worth every penny. I personally think that if you're looking for a Carbine optic and do not want to drop the cash on the Mark 5HD 2-10, this is a pretty good option at half the price and six ounces lighter with illumination, but it also has about half the zoom power.