Holding for Elevation, Part I

Last month we discussed trajectory.  We understand that the bullet only crosses our line of sight (crosshairs or front sight) at one or two points during its flight.  We can’t always shoot from the exact range of our rifle’s zero.  There are three options for dealing with this that I can think of:

 

     Option 1:  Use a point blank range zero, as discussed in the trajectory article.

     Option 2:  Adjust your sighting system to be zeroed at the distance that you’re 
                     presently shooting at.  

 

     Option 3:  Compensate for the variance of actual shooting distace to zero distance by
                     holding your sight over or under your target to align the bullet’s trajectory to
                     hit the target.

The point blank zero concept is practical for some applications, especially hunting.  It’s fast and simple.  You do your thinking beforehand and just shoot when it comes time.  The catch is that you’d better stay within the maximum point blank range.  That means that if you want clean, ethical kills on game your range estimation skills had better be good under pressure.  A major drawback with this approach is if you would like to have the ability to take a more precise shot on occasion, you’re kind of stuck with hoping to get lucky.

 

Adjusting your sights (aka “dialing”) is theoretically the most precise way to adjust the rifle’s trajectory for a change in distance.  This allows you to use your normal sight picture the way that the sighting system was intended to be used.  The primary disadvantage is that this is slower than either of the other options.  If the initiative is yours, than you might have time to adjust your elevation knob.  If the target is one of opportunity, you will be unlikely to have time to be cranking your knob.  

 

If you have a hunting scope, you probably have a capped turret, which you would have to take even more time to remove.  Under some of these capped turrets is a dial that takes a coin or a screwdriver to adjust.  Obviously, this type of adjustment is meant to be left alone in the field.  This eliminates dialing for practical purposes for users of those scopes.

 

This leaves holding.  The main thing with this technique is that you have to really have your trajectory down to the point where you don’t even need to think about it.  This is going to take a lot of shooting to get right.  Depending on what equipment you have and what your zero is, you’ll probably have to use holdovers for distances very close (before your bullet’s initial intersection with the sight) and then beyond your zero range.  For distances between your initial intersection and your zero range, you’ll have to hold under.  This is going to be confusing unless you have done it in practice a lot.

 

The easiest way to use elevation holds is with a calibrated reticle.  There are some that are supposed to be pre-calibrated to match a specific load.  It’s a cool idea, if you don’t mind being stuck with that exact load.  If you use a different load, or you have a different muzzle velocity, it could still work for the most part.  It just seems like an inflexible, and likely inexact approach to holding.  Reticles calibrated for loads tend to work best within about 500 yards. 

 

A much better way, and the optimum way in my opinion, would be to use a reticle calibrated in mils or moa, preferably with the scope adjustment knobs matching the reticle (mil reticle/mil knobs, or moa reticle/moa knobs).  This way you can know the precise hold for any load.

 

Here’s an example of how this might work.  Let’s say you use a 100 yard zero, and you find your target at 330 yards (you know this because you studied the crap out of the Google map for your AO).  Either by memory or by a reference card you know that your comeup is 1.5 mils for that range and zero.  Since your scope has a mil reticle and mil knobs (LUCKY!!!), you could either dial 1.5 mils up, or holdover 1.5 mils.  Because you’re in a hurry, you choose to holdover.  If you use a mildot reticle, you’d just hold over so that your point of aim is exactly between the first two dots on the vertical line under your crosshairs.  New reticle designs have hash marks, long hashes for full mils and shorter for half mils.  That would mean that you’d have an exact intersection to aim at, and precision would not likely suffer.  Press trigger, bang, hit… uh, that was pretty cool.

Even with a mildot reticle, reading it to the nearest tenth of a mil is not that hard.  You need to be able to read your reticle to at least that level of accuracy to range with it.  A good place to get some practice reading a mil or moa reticle is with the Shooter Ready long range shooting simulation.  This program is a lot of fun to work with and will get your reticle ranging skills up to par.  You can also practice using holdovers once you determine the range to target.

 

I hope this illustrates the advantages of the matching reticle and knobs, which in my opinion are huge, and increase the capabilities of your shooting system beyond the scope of this article.  As far as holdovers are concerned, the advantages of this system are that you have exact reference points for any range within your maximum effective range, especially with some of the mil reticles with 15 mils of holdover markings (this is equivalent to 51.5 minutes, and would be plenty to over 1000 yards for my modest 30-06 load, and out past where my load goes subsonic.  The advantages outside of the scope of this article include, but aren’t necessarily limited to, range finding, holding for wind, and engaging moving targets.

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