HFT – Scope Settings

This is the final part of my mini scope series, intended for beginners to HFT. In this post I will be looking at how to set your scope up specifically for HFT. The main theme here will be ‘personal preference’ so apologies if I repeat that  lot. I will mention my generic setup, to get you going though.

This post has again been kindly sponsored by In Your Sights. The 10% discount code still applies on everything on their website (including all of the scopes). See the end of the post for the code.

If you haven’t seen the previous parts to this post you can find them in the links below:
Part 1
Part 2

As we know, you aren’t allowed to adjust your scope in HFT. This is why you have to write down your magnification and parallax settings on your scorecard before you start shooting. You can’t write down your windage and elevation positions, but don’t touch these either!
This means you need to chose one setting for every distance from 8 to 45 yards. In this post I’ll try to give you the information you need to work out what settings you should try.

Eye Relief
This one is easy. Set it up how I showed in Part 2 of this series, then leave it. There are no sneaky tricks with eye relief that will give you any kind of advantage. Set it and forget it.

Ocular Lens Adjustment
Exactly the same as eye relief. No advantages to be had here. Get it just right for your vision, then leave it alone.

Parallax Distance (Adjustable Objective)
As I mentioned in the last post, this effectively sets the range at which both the target and the reticle are in perfect focus. Outside of this range, things will get progressively more out of focus, or blurry. So the big question is, what range is best? 
In short, there isn’t really an answer. It will depend mostly on personal preference and what you want to achieve with your parallax setting.
You could set it for longer range targets to avoid parallax error. Remember, any parallax error will be worse the further away the target is. This is handy if you struggle to shoot consistently at 35-45 yards, or you have a rifle/stock/scope combination which doesn’t fit you very well. Ideally you would have a good fitting stock and scope, but this isn’t always possible for beginners or people on a budget. This will make the closer targets much more difficult to see, but plenty of practice and maybe lower magnification will help.

The other, more popular option, is to use the parallax to help with range finding. This is done using the fact that a known range of distances will be perfectly in focus. Depending on the scope you could expect this to be around 5 to 10 yards of perfect clarity (maybe more as the scope price rises). As the targets get further away from this range, they will get progressively more out of focus. 
What I mean by perfect clarity is that both the target and the reticle are focused at the same time, and both look crisp and clear. When you look at targets closer or further away, your eye will chose either the reticle or the target to stay locked on to and the other will start to blur. It is possible to force your eye to switch focus between the two. This comes more naturally to some people but is worth practising. Personally I prefer to keep the reticle sharp, and let the target blur.

Some people like to have the furthest targets (40-45 yards) slightly clearer so they can see the kill zones properly. This is useful if you find these distance shots difficult, and will also help with parallax error (see above).
Other people prefer to have the closer targets in focus (15-20 yards). This can help with the 15mm kill zones. These are the smallest on the course and are some of the most commonly missed targets. This means the area all around the kill zone gets the paint knocked off, making a large grey patch. Through a blurry scope the dark coloured kill zone and this grey patch can seemingly blend together and make it hard to see where you should be aiming.

The other option (and the one I use) is to have it somewhere in the middle (around 23 yards). I find this the most useful for range finding.

The pictures below should help explain what I am describing. The first shows perfect clarity of the reticle and the target. Then the target gets more out of focus as you get closer to it (or further away).

Zero distance
This is the distance (or distances) at which the pellet will strike exactly in the middle of your reticle. For targets closer or further away than your zero range, you will need to ‘hold over’ or ‘hold under’. This means aiming higher or lower than where you want the pellet to land.
The reason for this is that the pellet will fly through the air in an slight arc, or trajectory. Initially it will seem to rise coming out of the barrel, reach a peak in it’s curve, then start falling again. 
Setting your zero distance is also down to your own preference. There are pro’s and con’s to all of the options which you might hear about and it’s probably best to try them all before picking. However when you do chose one, I would say stick with it and really get used to it. Constantly changing your set-up won’t help consistency.
Setting the zero at the high point of the trajectory means you won’t need to hold under (aim low). This can simplify your aim points, and avoid any mistakes where you forget which direction you are meant to be aiming! This is usually around 23-25 yards for a .177 pellet in a 10.5 to 12 ft-lb airgun. The graph below shows the trajectory of a 25 yard zero across the HFT ranges.

Setting the zero just before the peak, has the effect of flattening out the trajectory so you can aim using the centre of the reticle over a slightly larger range of distances. In reality the pellet will strike slightly high at 25 yards but with most targets, the pellet will still land in the kill zone.
With a 25 yard zero, the pellet might be aimed flat from 22 to 27 yards. But with a 22 yard zero you might be able to aim flat from 19 to 30 yards. This also slightly reduces the holdovers at the closer and further ranges. 

Setting a zero further out, for example 30 yards, gives you another zero at around 15 yards. This further reduces the hold overs at long and short ranges, but means you will have to hold under at ranges inbetween. 
See the graphs at the end of this post for an example.

For any beginners, the following pictures show aiming dead on (what I call ‘flat’). Then hold-over and finally hold-under. You can see how getting these the wrong way round could make you miss quite easily. This is one of the reasons I don’t use hold-under.

Magnification
The usual advice here it to set the magnification to give you the best compromise between the 8 yard and 45 yard targets. Generally this ends up being around 8-10x. This should allow you to see the kill zones at all the distances, without the closest targets becoming too out of focus. Turning the magnification down will make the closer targets a bit clearer. Turning it up will make the further kill zones appear larger in your field of view. If you are changing the magnification, you will probably need to re-adjust your parallax settings to suit.
9x or 10x magnification would be a good starting point and are probably the most widely used.

Aim Points
This is easily the most important part of setting up your scope for HFT. It doesn’t matter what combination of parallax, magnification and zero distance you are using, this needs to be done.
What we are trying to achieve is to work out how much hold over (or hold under) we need to give the target at each distance. Ballistics programs on computers or phones, can give you a rough idea but they should not be used on their own as they will very rarely be 100% accurate. There is absolutely no substitute for getting to a range and shooting paper.
What you need to do is set the zero to your chosen distance, then shoot paper targets at 8 yards, then at least every 5 yards after that, up to 45. 12 yards is also worth doing if you have a loopy trajectory at close ranges. The more ranges you can do, the better the results will be. Aim for the centre every time, and make sure your target has a few inches of clean paper above and below the bullseye.

If you are a crack shot, you will clearly see nice groups of pellet holes in the paper. Simply look through the scope and see how far under (or over) the bullseye they are (using the mil-dots as your reference). If you struggle to group the pellets well, especially at the longer ranges, try to take the average for now. Then repeat the process as you improve.
If you don’t have access to a long enough range, shoot as many different distances as you can, and use a ballistics program to fill in the blanks. You must make sure your inputs are correct though.
This picture shows the general idea. It’s only 10 to 16 yards but the change in point of impact can clearly be seen.

I tend to round my aim points up or down to the nearest 1/2 mil dot. This suits my skill level, plus I find it easier to use the 1/2 mil dot marks to aim with. Trying to aim in between the dots isn’t for me. My aim points are below. This is with a 0.177, at about 770 fps and 10x magnification.

8 yard = -2.5 dot
10 yard = -1.5 dot
12 yard = -1 dot
15 yard = -0.5 dot
20 yard = 0
25 yard = 0
30 yard = 0
35 yard = -0.5 dot
40 yard = -1 dot
45 yard = -1.5 dot

One trick I sometimes use is to fine tune my magnification for the 45 yard aim point. If my 45 yard hold over is -1.25 or -1.75 mi dots, I will increase or decrease my magnification slightly to force the hold over to be -1.5 or -1.0. 

Scope Mounts
Scope mounts are available in a range of different heights. The different heights change the distance between the axis of the barrel, and the axis of the scope. Choosing mounts is a combination of what will actually fit, and how you want to affect your trajectory.
In general, lower scope mounts will make the pellet trajectory flatter at close ranges. However the objective bell of the scope will limit how low the scope can be mounted before it contacts the action or barrel.
Higher scope mounts will make the pellet trajectory flatter at longer distance. There is no limit to how high you can go, but there will be a point where there is no longer any benefit.
The graphs further down show this difference quite well.

Summary
I think the best way to summarise the above, is to say compromises have to be made. Different setups will make different ranges easier to shoot. The trick is working out where you need the most help.
Below I’ve put together some example trajectories, with point of impact shown in inches and mil-dots.
These are all based on a .177 at 11 ft-lbs and 10x magnification. The first graphs show the same setup but with different zero ranges. You can see the shape of the curves don’t change, they just get shifted up or down. These are the kind of changes a beginner with limited kit and budget can easily make.


The next graph shows how the shape of the curves can be changed by using different height scope mounts. This is more advanced and I would only recommend doing this once you really know where you need to make improvements.


As I said at beginning, most of this will be down to personal preference. It took me months of shooting HFT before I really started to worry about the scope setup, so don’t worry too much about it at the start.

I’ll end with what I think are the two most important pieces of advice:

  1. Don’t change your setup every time you get a low score or see someone else using different settings. Consistency and learning how to use what you have is most important
  2. Don’t let any of this spoil the fun of HFT. If it stops being fun, it’s not worth doing

Thanks again to In Your Sights for sponsoring this post. They are offering 10% off anything on their website (www.inyoursights.co.uk) with the discount code TheAirGunBlog119

I actually used one of their scopes to take some of the photos in this post (the Atom Optics 4-16×40 IR). I am currently doing a ‘technical review’ of this scope which will come in two parts and should be out sometime in the next few weeks. 

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