scaling down a target face size

Hi folks,

If you wanted to make a target face to be shot at 20yds that simulated the size of a 122cm at 100yds -

This is just as bit of fun to let beginners get a general flavour for relative size difference when shooting at 100yds - (I know this excludes the effects of wind, rain, drag, the magnification of a bad shot and all that stuff all of which is amplified at 100yds - that's not the point here).

A) Would you go by reducing the circle diameter by 5:1, because this would represent reducing the distance from centre to the edge of a ring by 5:1 - and hence difficulty in terms of relative accuracy to a fixed point of aim?

or

B) Would you reduce the circle area by 5:1 - because it's the circle (or annulus) area that represents likelihood to hit it?

This is purely a mathematical type question for a bit of fun - and not seeking advice on the advisability or relevance/value of doing this - thanks.

thanks very much in advance
 

chrisnoble

New member
I have often pondered the same question and there must be a mathematical solution. Thinking about two divergent lines from the archers shooting position out to 70 metres and beyond it would be the diameter which changes. Haven't done the calculations but I would be surprised if it's as simple as a 1:5 ratio.


Sent from my iPad using Tapatalk
 

Del the Cat

Well-known member
Reminds me of the time a drew a mock up keypad 2:1 and took it to be a print shop to be scanned, reduced to half size and printed.
They reduced it to half the area!!!! I was not amused.
They re-did it, but moaned that in their idustry that was how they worked.
This whole topic causes endless confusion... even in making bread... leave it until it has risen to twice it's size... errr? is that twice the volume or twice the linear dimensions which would be 8 times the volume.
People are often very poor at being explicit.
As they say oop North
They are all daft except me 'n thee, and I'm not too sure abaht thee ;)

Back to the question, it's simple geometry, like Kid Curry said angles. Just draw it out to scale if you aren't sure, but compress the horizontal scale more for convenience, say 1cm to 1yard horizontal and 1mm to 1cm vertical
Del
 
Answer A ... because the angles must stay the same
thanks Mr K - (and Del) that was my first thought too - seems logical - but then I had second thoughts - and then went round and round on it.....

I thought diameter was key because that means that if you were to get a disc at 20 yds to exactly occlude a ring at 100yds - it would be 5:1 diameter of the ring; and not its 5:1 area........

cheers
 

Mark31121

Member
Ironman
There is a powerpoint file somewhere out there that does this for you (tiny targets), unfortunately the link on Texas archery isn't working...

Whilst area may seem logical at the end of the day it's all about how far you're away from the centre of the target.
 

Rik

Supporter
Supporter
if you want it to look the same, then it's the linear dimensions that change (to keep the angle subtended the same).
If you want to shoot the same way as at 100 yards, then you should print two mini faces, one above the other. Aim at the lower one with your 100 yard sightmark and check the results on the upper one. If you can fit both on a boss at 20 yards....

If you want comparable scores, then it's a little trickier, as you would probably have to make the face a little smaller than the linear reduction would suggest, as the shorter distance would probably lead to relatively higher scores on a strictly scaled face.
 

kennyp

New member
Hi folks,

If you wanted to make a target face to be shot at 20yds that simulated the size of a 122cm at 100yds -

This is just as bit of fun to let beginners get a general flavour for relative size difference when shooting at 100yds - (I know this excludes the effects of wind, rain, drag, the magnification of a bad shot and all that stuff all of which is amplified at 100yds - that's not the point here).

A) Would you go by reducing the circle diameter by 5:1, because this would represent reducing the distance from centre to the edge of a ring by 5:1 - and hence difficulty in terms of relative accuracy to a fixed point of aim?

or

B) Would you reduce the circle area by 5:1 - because it's the circle (or annulus) area that represents likelihood to hit it?

This is purely a mathematical type question for a bit of fun - and not seeking advice on the advisability or relevance/value of doing this - thanks.

thanks very much in advance
Have a look at the app XRing scoring. There is a tab on there that does all the work for you
 

KidCurry

Well-known member
If you want comparable scores, then it's a little trickier, as you would probably have to make the face a little smaller than the linear reduction would suggest, as the shorter distance would probably lead to relatively higher scores on a strictly scaled face.
Line cutters will be your enemy unless you shoot over 1" dia. arrows at 100 yds :)
 

Rik

Supporter
Supporter
Line cutters will be your enemy unless you shoot over 1" dia. arrows at 100 yds :)
yes :) hence trickier. I'm not sure I would be able to figure it out except by trial and error - and there's a possibility that it's not possible to make one, for combinations of shaft size and shooting standard.
 

Senlac

Supporter
Supporter
So, to replicate a full size (122cm) face at 100yds...
- use a Portsmouth (80cm) face at 49yds [in fact close to a WA1440's 50m distance]
- use a Bray (40cm) face at 32yds
Correct?
 
Thanks again Gents - these points are all very true.

But, I don't intend to replicate a 100yds round or even what it's like to shoot at 100yds outdoors - it's just to give a few beginners an idea of the scale - and a bit of fun for a few arrows - its not a serious attempt in replicating 100yds shooting at 20 yds - but your comments are much appreciated - thanks

Anyways i made up a dozen faces on A4 (blue-gold rings only) - and I already wrote on these lots of caveats etc to explain why the real thing is much harder

cheers and thanks again

alan
 

fbirder

Supporter
Supporter
I have a set of targets by a company called ArchersMOA that are designed to look the same size at varying distances. So a size 2 @ 20yds, is the same angular size as size 4 @ 40, size 6 @ 60, 8 @ 80 and 10 @ 100. However, the company web site is no longer in existence.
 

Rik

Supporter
Supporter
Thanks again Gents - these points are all very true.

But, I don't intend to replicate a 100yds round or even what it's like to shoot at 100yds outdoors - it's just to give a few beginners an idea of the scale - and a bit of fun for a few arrows - its not a serious attempt in replicating 100yds shooting at 20 yds - but your comments are much appreciated - thanks

Anyways i made up a dozen faces on A4 (blue-gold rings only) - and I already wrote on these lots of caveats etc to explain why the real thing is much harder

cheers and thanks again

alan
It's always fun to speculate... I have an A4 PNG somewhere with 9 or so mini faces on it - sized to roughly simulate 70m face sizes at about 3 yards... That:s about all I can fit in, in the garage...
 
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