Discovery Optics MS 4–16×44 SFIR – Detailed Overview
The Discovery Optics MS series is the brand's entry-to-mid-range line, designed specifically for shooters who want a reliable optic without paying a premium price. The MS 4–16×44 SFIR is one of the best-equipped models in the series: wide magnification range, side parallax adjustment, illuminated reticle, and lockable turrets — all in one compact package.
Optics and Image Quality
The scope uses a fully multi-coated (FMC) lens system that makes efficient use of available light. The 44 mm objective lens makes a noticeable difference particularly in morning and evening conditions: the larger light-gathering surface delivers a cleaner, more contrasty image than smaller objectives. The field of view is 9.6 m / 100 yards at 4× and 2.4 m / 100 yards at 16×, which is in line with typical values for this category.
Reticle and Illumination
The reticle is glass-etched with MOA graduation and is positioned in the second focal plane (SFP). This means the reticle does not change in apparent size as magnification is adjusted — MOA values can therefore be read accurately only at maximum magnification. Illumination is available in red and green with adjustable brightness levels, making the reticle clearly visible against dark backgrounds or in twilight conditions.
Tube and Mechanics
The 30 mm one-piece aluminium tube allows for a greater internal adjustment range compared to 1-inch (25.4 mm) tubes. Total elevation and windage adjustment is 80 MOA each, which is more than sufficient for most use cases. The turrets are exposed, lockable, and zero-resettable, with tactile, audible clicks at 1/4 MOA increments. The construction is nitrogen-filled, making it waterproof, fogproof, and shockproof.
Side Parallax Adjustment
The side parallax adjuster — hence the "SF" in the model name — is one of the most significant advantages at this price point. Adjustment ranges from 10 yards (~9 m) to infinity, meaning the scope can be used accurately with an air rifle indoors and parallax correction can be applied at longer outdoor distances without image distortion.
Key Specifications
- Magnification — 4–16×
- Objective lens — 44 mm
- Tube diameter — 30 mm
- Focal plane — Second (SFP)
- Reticle — Glass-etched MOA, red/green illumination
- Parallax — Side adjustment, 10 yards (~9 m) – ∞
- Click value — 1/4 MOA
- Total adjustment (elev./wind.) — 80 / 80 MOA
- Field of view — 9.6 m (4×) – 2.4 m (16×) / 100 yards
- Exit pupil — 10.8–2.7 mm
- Eye relief — approx. 8–9 cm
- Length — 338 mm
- Weight — 617 g
- Construction — Nitrogen-filled, shockproof, waterproof, fogproof
What Is It Good For?
Air rifles (PCP and spring-piston): the 10-yard minimum parallax adjustment makes accurate aiming possible from as close as 10 metres indoors — a rare feature in this price range. The 4× lower end allows fast target acquisition, while the 16× upper end provides a detailed image.
Small-calibre rifles (.22 LR and similar): the 10-yard minimum is particularly valuable here, as these firearms are often used at shorter to medium distances. The illuminated reticle aids aiming against dark backgrounds such as dense foliage or shaded terrain.
Hunting and sport shooting: on small- and medium-calibre hunting rifles, it delivers balanced performance at distances of 100–300 metres. The lockable turrets prevent accidental adjustment during field use.
User Opinions Online
On English-language forums (Airgun Nation), a recurring view about Discovery Optics is that "the glass quality and value for money are convincing — you get good optics for the price, and I would buy one again." Several users also note that the scope is slightly larger and heavier than some competitors in its category. The MS series is specifically recommended by air rifle and .22 shooters, primarily due to the low minimum parallax adjustment.
(Source: Airgun Nation forum – airgunnation.com)
Who Is It For?
The Discovery Optics MS 4–16×44 SFIR is primarily recommended for beginner and intermediate shooters looking for a versatile, reliable riflescope at an accessible price. It is an excellent choice for air rifle owners, .22 LR shooters, and small-calibre hunters alike — especially when side parallax, an illuminated reticle, lockable turrets, and a 30 mm tube are all important, but the price of premium brands exceeds the budget. For anyone who does not want to compromise on the essentials but wants to buy at a sensible price, this riflescope is well worth considering.
