Rifle scope---Adjustment Concepts
Two basic families of elevation and windage adjustment assemblies are available with many different options in calibration and/or range of travel with more coming in the future. The same basics will be constructed for use in any short range (SN-4, -8, or comparable) scope, but also are applicable to long range scopes (SN-1, -2, or comparable). A selection of screw thread fineness (from 32 threads per inch, up to 56 T.P.I. or more) and alternative click ring serrations (from 40 notches up to 72 notches per revolution) will provide any degree of movement per click that is desired, from the coarse 1 M.O.A. up to 1/10 M.O.A. per click or anything in between. Length of the adjust screw is modified to give enough point-of-impact control for short range 50 M.O.A. adjustments, or to accommodate more than 150 M.O.A. travel that can be needed for 1000 yard or greater working range guns suited by the target models. U.S.#1 - The generic U.S. adjustment is comprised of a screw with integral clicker that is rotated by the knob to effect in or out motion of internal optical components which change point of aim. The clicker rides over a mating click ring with a series of notches around its periphery that produces a number of distinct, sensible and audible, detent positions. A broad foot is attached to the bottom of the screw, bearing on the movable optical assembly within the scope that changes reticle position in the field of view. The turret bushing houses all the elements and secures them to the scope body flat surfaces. A calibrated cylinder is created to display the increments of movement, and can be ruled to describe the ballistic profile of any variation in cartridge loading, barrel length, operating range, or any scope magnification setting. The height of the dust cap, knob, screw, click ring, bushing and cylinder defines the total travel capability and is limited only by the clearances between scope tube and internal tube. The knob rises and recedes to make the changes needed. The adjust knob is attached to the adjust screw through a tight, no-slip taper joint that is bound in position by a top cap screw, which allows the knob position to be reset on its datum once the rifle/scope boresight is achieved. U.S. #4 - This is a B.D.C. (Bullet Drop Compensatory) knob system. The exterior has the caliber and yardage increments from 100 yards or meters to 600 or 700 yards or meters, depending on how much bullet drop we can get in one full revolution of the knob. The thread rate and engraving must be custom made for each caliber. A blank spool and instructions for doing your own B.D.C. can be provided also. After perfecting your drop and establishing your line increments we can engrave the lines on your spool or an extra spool. This is a very quick system for rapid ranging. It is not an extremely precise system - no B.D.C. ever is. U.S. #8 - These novel and revolutionary non-rising adjustment assemblies are low in profile, and provide wide adjustment range in a compact package. The knob is joined to the adjustment nut, with its integral clicker, through a tapered interface secured with two small screws. Similar to the generic assembly above, the clicker rides over click ring serrations to give positive detents, however the click ring is shortened to take advantage of constant height elements. Only the screw, which is constrained from rotation by an axial pin, rises and falls as it is driven by the rotating nut/knob pair. The current design projects only 0.55 inches above the scope body flat surfaces, but can change the point of aim up to 100 M.O.A. in either direction from center in a typical 4x scope! This has never been achieved before to our knowledge.
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