Nikko Stirling Diamond Sportsman 10-50x60 Review

by Dale Foster

Well-known scope manufacturer Nikko Stirling has in recent years expanded its range of telescopic sights to cover most of the requirements of hunters and target shooters across the entire spectrum of shooting sports. The scope that is examined here, a 10-50x60 side-wheel focussing sight, has particular relevance to field target shooting, bench rest and long-range target rifle shooting.

The first thing that grabs your attention on opening the box is the sheer size of this scope at 46.8 centimetres (18.4 inches) in length it is big! After the size the next thing you notice is the weight, at 1130 grams (39.9 ounces) itís no lightweight either. However the bulk of this sight does pack in a lot of useful features. The scope is waterproof, fog proof and shock proof.

The scope is provided with a set of screw on lens covers, but there is no sunshade supplied. A call to the UK importer of these scopes confirmed that there is currently no manufacturer of sunshades to fit the 60mm front lens of this scope. In all fairness, however, the absence of a sunshade presented no problems during the duration of the test, which was conducted under a wide variety of light conditions. The fact that the front lens is quite deeply recessed into the objective bell appears to act as an integral sunshade.

The finish on the scope is a very practical and tough matt black anodising. When examining this scope the size of the saddle that carries the adjustment turrets is very noticeable, it is approximately twice the length of the saddle on many other scopes. The parallax adjustment is located on the left hand side of the saddle, but set forwards of the windage turret instead of directly opposite it. The parallax wheel turns smoothly through its entire range without stiffness or free play. There is no sensation of any backlash in the focussing system either.

A large side-wheel is supplied as standard on this scope making it eminently suitable as an FT scope. Distance figures are neatly engraved and highlighted in white, these align with a datum indicator that is attached to the side of the saddle. Given that the parallax adjustment goes from 10 yards to infinity this scope would also be at home on a full-bore rifle for use in bench-rest shooting or for F-class target rifle events.

The large side-wheel can be easily detached if it is not required by undoing two small socket headed screws. One small and easily overlooked feature is the presence of a small locating peg which engages into a recess on the large wheel that ensures that when the wheel is re-attached the range markings are in the correct position. Full marks to the designer for taking this into consideration.
The resolution of this scope is extremely good. I took the opportunity to use it in the manner of a spotting scope by mounting it on a tripod. Looking at a petrol filling station that lies over 600 metres from my rear window, using the full 50x magnification I was able to read a safety notice attached to one of the support pillars of the forecourt canopy that advises motorists to switch off the engine and not to smoke etc, the letters on this sign are approximately 3 inches high. Looking further afield, I was able to see the concrete triangulation pillar that is located at the summit of Carn Marth hill some 7.5 miles from my home.

The zoom ring turns smoothly but firmly through the entire magnification range. The numbers on the zoom ring are neatly and boldly engraved and highlighted in white, numbers are present for the major divisions i.e. 10, 20 etc, half way figures, 15, 25 and so on are indicated by an engraved line. The eye bell of the scope is equipped with a speed focus facility that gives a large range of adjustment to ensure a crisp view of the reticle for people of differing eyesight.

The windage and elevation turrets are of the external target type, featuring click values equal to 1/8 inch at 100 yards and vernier scales that allow the degree of adjustment to be easily monitored. When the scope has been zeroed at the desired distance, the turrets can be reset to the zero mark using an allen key that is supplied. Both turrets are large enough to allow for easy adjustment even when the shooter is wearing gloves

The reticle on the test scope is of a form known as the NATO range-finding reticle (a Mil-Dot reticle is also available in this scope), and is etched onto glass. At first glance this reticle looks not unlike a duplex reticle that is missing the top thick post. The horizontal thin wire features regularly spaced graduations either side of the centre cross and two graduations between centre and the lower thick post. At the bottom of the field of view is a set of range finding stadia marks. The paperwork that accompanies the scope contains a detailed drawing of the reticle with an accompanying table giving the value of the graduations in minutes of angle.

As the features of this scope are very well suited towards FT, this makes the logical starting place for field-testing the scope. One point that needs to be considered when fitting this scope is the outer diameter of the objective bell, given that it has to house a massive 60mm front lens the diameter of the bell is some 70mm, this will require the use of raising blocks on some rifles as well as high mounts. Such blocks are available from most of the manufacturers of scope mounts.

The scope focuses down to a minimum of 10 yards at the full 50x magnification, however, reducing the magnification allowed targets down to 8 yards to be brought into clear focus. The image snaps in and out of focus very quickly allowing for a rapid and efficient assessment of the ranges. It was easily capable of distinguishing between targets at 50 and 55 yards. Also, with greater familiarity than can be obtained within a limited test period, distinguishing increments of about 1 yard between 50 and 55 yards seems to be within the capability of this sight. The turrets showed accurate tracking during dialling for targets of different distances and they returned consistently to zero each time.

The large objective lens and full coatings on all the lenses contributed to giving a bright image across the entire magnification range, allowing targets in well-shaded areas to be clearly discerned. The reticle proved to be easily visible against all the dark targets that were encountered, while being fine enough to allow for precision aiming something that a bench rest shooter would appreciate. The presence of graduations on the horizontal wires provided very useful aiming off marks for wind compensation. One concern was that the weight of the scope might cause the rifle to handle awkwardly, but this turned out to be groundless as, if anything the stability of the rifle was improved by the addition of the extra weight.

In conclusion this scope has to be considered as a serious scope for top-level field target shooting due to its extremely good range finding capabilities and affordable price, it easily equalled the performance of a well-known brand of scopes imported from the USA, which have had great popularity in the field target arena. It is capable of being competitive straight out of the box without the need for any add on extras or alterations, other than the adding of range finding marks on the circumference of the large wheel to suit the eyesight and requirements of the individual owner. It also has great potential for use in other target disciplines on a wide variety of rifles where a high magnification telescopic sight is allowed.

I would like to thank A.S.I. for the supply of the test scope.

Technical Specifications:

Length: 468 mm
Weight: 1130 grams
Tube Diameter: 30 mm
Magnification: 10x - 50x
Reticle NATO Range Finding (glass etched), Mil-Dot also available
Adjustments 1/8 MOA  (1/4 will be available soon)

Objective Lens Diameter:

60 mm
Ocular Lens Diameter: 32mm
Objective Bell Diameter: 70mm
Ocular Bell Diameter: 43mm
Lens Coating Fully Coated
Diopter Compensation +/- 2dpr
Number of Lenses 13
Turrets External Target Type
Parallax 10 Yards to Infinity
Field of View 2 Degrees @ 10x, 25 MOA @ 50x
Eye Relief 83mm