"Setting Up An Air Rifle And Telescopic Sight For Field Target -An Instruction Manual For Beginners -BFTA"

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Trajectory Compensation by Holdover

What is holdover?

Holding-over is a method of trajectory compensation whereby, upon establishing a base zero, no further adjustments are made to the elevation turret from shot to shot when changing the target distance. Instead, all compensation is done by aiming high/low.

This is done in one of two ways. The shooter can directly aim high by a specified amount, for example: holding the central crosshair level with the top of the killzone. This requires the shooter to have good spatial awareness and to know how small distances such as an inch relate to the killzone on a distant target .

The second method is simply as refinement of the above. Instead of willingly putting the central cross somewhere above the target, the shooter will place some other part of the reticule in the centre of the target. The central cross will still be held somewhere other than the KZ, but the eye will be focussing within the crucial part of the target. This is usually facilitated by the use of a “Mil-dot”, or Multi-line reticule.

Multi-Aimpoint Reticules

The standard duplex (thick-to-thin post) reticule, while perfectly acceptable for hunting at short range, is found wanting when it comes to accurately compensating for trajectory.

This is where a multi-aimpoint reticule comes in. A “Mil-dot” reticule has, in addition to the thick/thin crosshairs, several dots spaced at intervals along the thin parts of the crosshairs. It is possible to use these to allow for pellet drop much more accurately than the standard duplex.

A multi-line reticule goes a step further. Instead of dots on the vertical crosshair, there is not one, but several horizontal lines, (or Stadia). One of these lines is used for the base zero, with the lines below it used for distances further from zero, and the lines above used for the zenith of the trajectory (if not zeroed at zenith.)

The first thing to consider is which distance you are going to use as primary zero, i.e: which distance coincides with the central cross. After that, it is simply a matter of shooting at zeroing boards from 8-55 yards, adjusting your aim for each range so that you know which part of the reticule you have to place in the centre of the target for any given range.

When using holdover it is not as important to optically centre the scope as it is when “dialling”, but it is still beneficial. Instead of centering at 10 yards it is done at the distance that coincides with the primary zero, since your scope will never be moved from that setting unless to re-zero.

Below is an example which shows how the dots in a mil-dot reticule can be used to give aim-points between 8 and 55 yards. It is not a precise example and is only given to illustrate the principle, because the placement of the points of impact within the reticule is completely dependent on the magnification selected. For this reason, shooters using holdover/multi-aimpoints tend to choose a magnification early on in their shooting careers and stick with it.

(The numbers and small horizontal lines would not appear in the actual reticule):