The History of Riflescopes

Aug 5, 2013 | Optics

By Pierre van der Walt

The Arabs pioneered the development of the telescope and had already manufactured telescopes in the eleventh century. This knowledge was lost somehow during the Middle Ages, probably due to the Crusades.

A Dutchman, Zacharias Janssen (1588 – 1630) rediscovered the knowledge during the 16thcentury.The news spread across Europe and by 1609 commenced building telescopes in earnest. By using a concave as well as a concave lens Galilei succeeded in viewing Jupiter’s moons. The lens combination furnishes an upright image and the system has since become known as the Galilian system.The German scientist Johannes Kepler (1571 – 1630) used convex lenses in both the objective and ocular positions. This provided a much larger field of view than the Galilian system, but the image with the Kepler system is not only inverted but hind part foremost as well.

Telescopes were installed on rifles for sighting purposes during the 17thcentury. The first reference to scopes on rifles is found in Francesco Lana de Terzi’s (1631 – 1687) Magister Naturae et Artis of 1684. King Frederick the Great of Prussia noted in 1737 that he had fired a telescoped rifle. Riflescopes naturally were very expensive and, therefore, gained little commercial acceptance for centuries. It was more popular (especially on sniping rifles) in Europe than anywhere else in the world, mainly because the necessary know-how was centered in Europe at the time.

The breakthrough came when the American, William “Bill” Ralph Weaver (1905 – 1975) succeeded during the early 1930s to manufacture and market rifle telescopes at an affordable price. Bill Weaver had no formal optical training and taught himself the technical aspects of riflescopes. He first manufactured a riflescope in 1931 and founded the W.R. Weaver Company at El Paso Texas during 1933 to manufacture affordable riflescopes. Weaver’s first riflescopes were not manufactured in Texas but in Newport, Kentucky, and were substantially smaller, lighter and much cheaper than their European counterparts, and became an immediate success.

Weaver experienced several serious problems. Virtually no gunsmith knew how to mount a riflescope onto a rifle. Production rifles of the period were not equipped with holes drilled and tapped for riflescope installation. Weaver had to mount all the riflescopes he had sold himself and soon realized that it was impossible. To overcome the problem he toured America training gunsmiths. As time progressed gunsmiths gradually took the burden off his shoulders, allowing him time to lavish his attentions on his primary enterprise. Rifle manufacturers also started drilling and tapping their rifles for riflescope mounting. Today we take these things for granted and mandatory, and it is hard to imagine a time when it had not been the case.

Weaver not only succeeded in making the riflescope available and affordable to the average man, but he initiated a brand-new industry and, in the process, selling more riflescopes by the time he died than any other rifle manufacturer in the history. The company fell on hard times and Weaver was forced to sell it in 1968. This process repeated itself for a number of years until it was sold to the ATK Sporting group that also owns Federal Premium, Alliant Powder, RCBS, CCI, Fusion, Speer Ammo, Speer Bullets, Estate Cartridge and Blazer.

Another factor that troubled Weaver was the shape of the bolt handles of the rifles available at the time. The shape prevented bolt manipulation once a riflescope had been installed, as most protruded rather sharply from the bolt shaft. He solved the problem by either mounting the riflescope far enough ahead of the bolt handle’s path to allow the handle to pass behind the ocular bell, or he altered the bolt so that it could pass underneath the riflescope. The latter option became the more popular and nowadays virtually all manufacturers design their rifles to allow normal operation, even with a riflescope in place.

Adjusting riflescopes was a problem in itself. Most riflescopes were internally adjustable for elevation only. Adjustments were not calibrated and no pre-determined adjustments were provided on the early riflescopes. Windage could only be adjusted externally. In other words, the vertical crosshair could not be adjusted. The entire riflescope had to be moved sideways at the rear mount and this caused problems. The riflescope was firmly clamped in the front ring and any lateral adjustment of the rear part of the riflescope bent the riflescope. Bending it, placed the tube as well as the lenses and seals under stress,often resulting in breakages. Apart from that, it had a detrimental effect on the path which the light rays followed through the riflescope.

Mounting holes were seldom perfectly aligned, resulting is slightly askew base positions. Manufacturing tolerances resulted in variances in the height differences between receiver and bridge. Reticules in the early riflescopes were only in the rarest of cases exactly centered in the riflescope image. Shims were used to offset such errors and to move the reticules nearer to the centers of the image seen through a riflescope. In due course the permanently centered reticule made its debut. This development compensates for slight installation errors whilst keeping the reticule intersection in the exact centre of the field of view. It would be an understatement to say that permanently centered reticules was one of the most important and welcome steps in the development of the riflescope.

At the outbreak of the Second World War American riflescopes had become adjustable on both planes. This was not the case with European riflescopes, though. Today we are fortunate in that apart from having riflescopes which are internally adjustable on both planes, we also have adjustable mounts which allow lateral movement of the riflescope’s rear without warping it. Minute and extremely accurate adjustments are, therefore, possible nowadays.