Optimal Optics: Comparing Tactical Riflescopes
March 25, 2013
Until shockingly recently, fighting rifles wore iron sights and nothing else. And that went for the soldier carrying a .58 caliber M1861 musket while preserving the Union, an M1903 Springfield "over there" or an M16A2 liberating Kuwait. Not so today, with battle rifles increasingly wearing versatile low-magnification variables scopes. To gain some insight into the numerous examples available, I selected nine different commercial models. All are intended for use on AR-15s or similar designs. Models ranged from economical to fairly expensive. Each was subjected to the following test:
- Submersed in water to a depth of 18 inches for 12 hours
- Subjected to a steam bath for 15 minutes
- Cooled in a 20 degree environment for 24 hours
- Heated to 130 degrees for 12 hours
- Test-fired on a 7 pound .458 SOCOM with 405-grain handloads to induce stress. Ten rounds, rapid fire.
- Test-fired to check mechanical adjustment accuracy and consistency at 100 yards.
A bit to my surprise all 10 examples passed these tests without issue. None fogged internally or suffered from a mechanical issue. All of them tracked consistently. How well their tracking holds up under hard and long-term use though is beyond the scope of my testing ability. However, to be fair it's doubtful a rifleman would be dialing in windage or elevation with a scope of this type in the field. They are designed to provide rapid hits, and once properly zeroed, riflemen simply hold off for wind or distance.
Next I checked the optical performance and reticle illumination of each scope in bright, overcast and low-light conditions. I measured field of view and eye relief and also checked the reticle designs against a man-size silhouette at 50, 300 and 700 yards at highest and lowest magnification settings. The results were then tabulated and scored on a scale of 1 to 10.
Find all this and more on the accompanying charts:
Decades ago the environmental tests performed for this article would have proven very difficult or impossible for most riflescopes to pass. Times change, and with the advancements in sealing technology all the scopes shrugged off these tests as if they were nothing.
Optical performance has also come a long ways.
Lens design and coatings have made constant strides that have trickled down into economically priced models.
Today the big push is to increase magnification range and reticle intensity. The smoke is already visible on the horizon, and the models of tomorrow will be even better.
When it comes to optical sights, we live in exciting times.