Rangefinding in HFT (help needed)

Discussion in 'Hunter (HFT) & Field Target (FT)' started by Danladi, Jul 16, 2009.

  1. Danladi

    Danladi New Member

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    Hey guys,

    I'm going to my first HFT meet a week on sunday @ baldwins gate. I've been practising shooting my harrier alot lately (about 1500 pellets in the past week, thought this was meant to be a cheap hobby lol). I'm feeling confident that i can hit a target 95% of the time providing i know the range.

    ...and that's the problem. Although i understand a lot of it is gettnig out there and doing it. But I still like to know as much as possible going into it so time isn't wasted. What is the most effective means of rangefinding in HFT? i'm using the MTC viper scope with SCB reticle.

    If it's just a matter of basically guessing the range based on previous experience then fair enough, but if there are any good methods of rangefinding for noobies, i'd love to know.

    The main thing that comes to mind for me is the bracketing method using the reticle. The problem i can't seem to overcome is that the killzone of knockdown targets will vary in size, meaning i can't simply measure how big the killzone is in mil's and read the range off of a range card. Is the plate of the target a consistant size? Could that be measured in mils in order to range find?

    I know some people intentially blur certain ranges in order to guess the range, but my scope is pretty clear at most distances between 8 and 45 so i'm not sure that is doable.

    any help is much appreciated! :)


    cheers, dan
     
    Stephen likes this.
  2. Brian.Samson

    Brian.Samson Allowed in Sales Staff Member

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    Rangefinding in HFT is a huge subject so I won't go into great detail since you're new to the sport and I wouldn't want to scare you off..

    Since you've asked about bracketing though, I can tell you that on a standard Nockover target (the most common target used in HFT and FT) the distance from the top of the hinge plate to the centre of the killzone is 110mm (except a 15mm Squirrel target which is about 112mm). You can also take measurements of each different target type and produce a range card from that.

    But.... this isn't a particularly reliable method for lots of reasons - firstly, taking precise measurements in mildots isn't easy. It's extremely easy to make a mistake on your reading which will put you miles off on distance. Secondly, this is a well known method by course designers who will deliberately throw in a curve ball target to really mess with your head.

    It can be a useful method if used as a last resort, but shouldn't be used as a primary method of range finding.

    There are a number of methods however... including the good ole Mk1 eyeball (which also shouldn't be totally relied on either because course setters will also place targets to fool those that range by eye).

    I'll briefly list some of the various methods...

    1. Learn the rules of course setting - if you see a 25mm killzone, knowing the rules will tell you that it cannot be any further than 35 yards for example. Similarly 15mm kills will be between 13yards and 25 yards.

    2. Learn from previous targets - once you've shot a target and seen where your pellet landed, that should give you a very good clue as to the exact distance to that target. You can then use that target as a reference for other targets on the course. If a target was 40 yards on a large tree for example and the next lane has a target that's a bit further than the tree then you'll know it's over 40 yards etc.

    3. Look for reference points on the course - such as targets placed on or near fencing with equally spaced posts (as most are). You can't pace the distance to a target but you can pace the distance between two fence posts behind the firing line and then multiply that by the number of posts between the line and the target - there are other examples of this which I won't go into, but you get the idea - keep your brain engaged and look for clues and reference points.

    4. Bracketting - you can bracket killzones, hinge to centre of kill, full faceplates, partial faceplates etc etc.. this can be a handy method as a last resort or to double check the range, but use it sparingly and don't trust it if a more reliable method is available.

    5. Ranging by eye (be aware that targets in a tunnel of trees will look further away, targets where there's dead ground between the target and the line will also look further away).. There are lots of ways that rangefinding by eye can be fooled, experience will help you to learn when this is likely to happen.

    You can practice this method while walking down the street etc.. try to judge the distance to a lamp post for example and then pace it out to see if you were right or wrong etc.. try not to do this in a crowded area though or you'll get some strange looks :)

    6. Rangefinding by parallax - as you mentioned, you will notice that at certain ranges the image of the target and the crosshairs will both be in very sharp focus. The MTC viper has quite a poor depth of field so although you say it's "pretty" clear between 8 and 45 yards, with practice you'll learn the difference between pretty clear and crystal clear and be able to use that to help with rangefinding. You can practice this by first concentrating on the traget then on the crosshairs.. if you notice that your eyes have to re-focus when switching between the target and crosshairs then you'll learn how to tell the difference between sharp focus and blurred focus. It does take practice, but this is the most reliable method of rangefinding in HFT (and it's the method used to rangefind in FT as well).

    Another way you can use this method is - suppose your scope is in sharp focus at 23 yards and you are able to get that distance about right within a couple of yards.. you can then use that focus range to look around for things on the course such as trees etc that are at exactly 23 yards - this will give you a good reference point that can then be used to judge the distance to the target.

    Something else for you to consider... You don't have to hit the target in the centre of the killzone for it to go down, so if you're wrong by a few yards it doesn't matter.. instead of trying to come up with a single distance for a target try to come up with a range of ranges so to speak... for example you might think that a target is between 30 and 37 yards... have a look at your aimpoint for 30 and your aimpoint for 37... can you get both aimpoints inside the kill? - if so hedge your bets and shoot the target for 33.5 yards.

    I said I wouldn't go into great detail didn't I... Ooops.. :D
     
  3. RobF

    RobF Administrator Staff Member

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    I'm glad someone asked this question... i had hoped there'd be something in there I hadn't thought of that made life easier... damn... it looks like it's skill and hard work! :D
     
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  4. Danladi

    Danladi New Member

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    cheers for that, it's a lot of food for thought!

    hasn't scared me off don't worry! it seems like it's best to use more than one of these methods at any time to get an accurate-enough range estimation.

    bracketing from the base-plate to the centre of the kz seems like a better way of doing it. at least that is a fairly consistant size. I find the scb-style reticle alot easier to measure sizes with than the more standard mil-dot i had on the gun previously. But it is still easy to make a mistake with it I agree. definately combining with some other methods is the way to go.

    was hoping for a quick and easy fix but ah well i'll stop being lazy :p practise practise practise it is then.
     
  5. skipper

    skipper New Member

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    The missus and i (lou ,Girly-scorpion) walk everywhere guessing ranges especially when walking the dog and i mean everyday :):D:shot: we argue alot (light hearted) with the air tinged with '....NO way is it...'

    Get a 10 yd Marker in your minds eye then use a tree ,rock etc to find the 10 yd increments (if thats the right word)

    The above post is brilliant though :)

    Ollie
     
  6. Feral

    Feral New Member

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    With this and Robs post on standers we're having a good week for potential stickies, excellent post Brian!
     
  7. Charlts

    Charlts Getting dusty

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    It's when Mead/Gamo/home made targets get thrown into the mix then becomes tricky. If I'm ever unsure, which is often as my range finding is rubish! I'll either bracket it, check the blur to give me a best guess and then cram as many aim points in as possible. Luckily I'm better at guessing wind than distance!:D;)

    The best way is by eye but there's only a couple of people who are much good at it and it comes from experience.:);)

    Ryan
     
  8. popsheep

    popsheep Lee Marvin & the Shadows

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    Brian Sampson

    The man that got me involved in UKAHFT,I knew I was listening to the right man when I first met him .
    What a great post to help othesr get the best out of the sport
    well done sir
     
  9. Brian.Samson

    Brian.Samson Allowed in Sales Staff Member

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    I have more than a little bit of experience of bracketing I've got to say :)

    It was me that told Gary Cooper about the hinge to centre of killzone method probably about 4 years ago now, and I also had some input into the design of the SCB ret - the floating crosshair for example was my idea.

    The difficulties with bracketing are that it's easy to miscount the number of increments - especially when you're in the middle of a competition when the pressure is on. It's also not always easy to keep the rifle perfectly still while taking a measurement and a difference of even 0.2 of a mildot is enough to put you waaaay off on range.

    I wrote a training manual on this subject years ago and I also developed a quick online quiz to help shooters practice this method.

    Here's a test to help illustrate some of the difficulties you'll face when trying to bracket a target.

    > Online Bracketting practice test < (Your browser will need to support FLASH in order for this test to work)

    Measurements are taken from the Top of the hinge plate to the centre of the killzone - there's a range card next to each example for you to read off the range from - see how accurate you and perhaps post the difficulties you find by doing this test and what method you used to overcome those difficulties.

    Hint - the hinge plate is about an inch higher than the baseplate.. it's clear to see on some targets, not so clear on others, but these are real photo's of targets from a real course - so this should help to illustrate that bracketing isn't as simple as it seems.
     
    Last edited: Dec 3, 2010
  10. RobF

    RobF Administrator Staff Member

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    That is a superb little thing there!... had a go myself... got them pretty close, most within a yd, but you can see how the mistakes you've mentioned can be made (I did on the first one) and just how damned accurate and still you'd need to be (not always possible)
     
  11. Brian.Samson

    Brian.Samson Allowed in Sales Staff Member

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    Something that the test doesn't illustrate and it's probably the biggest cause of inaccuracies is this...

    The human eye/brain can concentrate on one thing at a time (or maybe that's just me?) so for example you might decide to use the thick part of the bottom post of your ret as the starting point for your measurements.. you concentrate on aligning the post with the top of the hinge then start looking up the ret to take a measurement. As you do this you'll find that you naturally start lifting your rifle up as well - giving you an incorrect measurement. You really need to be able to concentrate on both the start point and the end point at the same time and make sure your gun is perfectly still throughout. It's alot easier to do with a mouse on a flash demonstration than it is in real life on a course.

    You only have to be out by a fraction of a mildot and you're far enough out on the range to miss the kill.
    It's even worse trying to use this method in SFT out to 55 yards.. fortunately there's a more reliable method for SFT - if you're not sure how far the target is, it's probably 55 yards :D
     
  12. Sam Vimes

    Sam Vimes New Member

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    Listen to what Bri has to say and you'll not go far wrong.;)
    Rangefinding needs to be done using every possible method at your disposal. Then you need to play the odds based on the information discerned from using all of the different methods. Relying on one method alone is a recipe for disaster. Once upon a time, and occasionally at some less well informed clubs, bracketing could be remarkably reliable. As clubs/coursebuilders have got wise to bracketing it's use has become less important.
    Chances are these days that I've already half decided (to within 2-5 yards) what range a target is before I even take my rifle out of its bag. Doesn't stop me using a bracketing chart even if it's often just for show!;):D
     
  13. rogb

    rogb Señor Member

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    Excellent work there, Brian! I, just like in normal HFT, was out by 1-5 yards, partly because I had trouble seeing the hinge to measure from.:eek::rolleyes:

    I have only one thing to say to you sir:D
     
  14. Danladi

    Danladi New Member

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    Ah that flash test thing is pretty cool. Is there a version of this training manual you have written online someplace?
     
  15. Brian.Samson

    Brian.Samson Allowed in Sales Staff Member

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    Yup it's :-

    >PDF Range Finding Training Manual <

    It was written a few years ago now, and things have moved on since those days - for example, there are far more home grown targets than there used to be, the minimum distance for a 15mm target is now 13 yards and the comment at the end about the faceplate method not being too well known is a little out of date - most people know about this now.

    Be warned, it's quite a lengthy document - there's a lot to wade through, if you're new to the sport it might be a bit off putting to read.

    There are a few additional methods I haven't documented, but I'm not giving away all of my little secrets :D

    It's still true however that the most reliable method of rangefinding is to use the Parallax trick - it takes some practice but it's the only method that course designers can't set traps for - it's also the method I used to use when I was out hunting. If Mr Bunny was blurred in my scope, I knew I needed to get a bit closer before taking my shot. Now I use a Laser Range Finder when I'm out hunting which makes life a lot easier.
     
    Last edited: Dec 3, 2010
  16. Danladi

    Danladi New Member

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    OK great i'll have a read of that.

    If anything more information is the opposite of offputting for me. maybe i'm just weird :p

    thanks again :)
     
  17. RobF

    RobF Administrator Staff Member

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    has anyone tried using parallax error to rangefind? i was just wondering if you can use the mildots against the shift to measure... if you move your head from side to side, from the extreme of losing the image, getting it and losing it again, there should be a movement of the image against the ret... and could this be measureable?

    funny enough, owls do this head bobbing (and some other birds of prey), because they have very narrow field of view that is almost monocular, and find judging distance difficult, so they head bob to see the parallax shift of their target against a background
     
  18. Mog

    Mog New Member

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    I feel you could have something there Rob. Only problems would be that each scope would be set up differently, some scopes seem to have more PX error than others, so no constants, as with bracketing with true mildots, and the fact that head movement would probably impart some rifle/scope movement, making measuring even more difficult.
     
  19. mr dink

    mr dink Member

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    The best article i,v ever read about HFT Brian ,the test is brill well done.
     
  20. simmmo

    simmmo Active Member

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    Great work Brian. Thankyou for sharing all that stuff.

    Andy
     

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