Target size?

[toojon]

Is a 1/3 size ISPC target at 10 yards the same skill as full size at 30 yards?

[benos]

We need some math-brained-minute-of-angle individual for this one. Detlef, Flex?

be

[DBChaffin]

I don't claim to have the skills of either of those fellas, but using a right triangle and doing the calculations, I would say that yes, a 1/3 size IPSC target at 10 yards is equivalent to a full size at 30 yards.  Anyone have a better way or show me I am wrong?

[grassy knoll]

i have been waiting to see somebody answer this as well, the thing that i think about is that we are not using 1/3 size bullet holes

[toojon]

This started with a site offering 1/3 size ISPC targets as a free download. I tried the targets today and I don't feel that practically the porportion is valid. I can shoot all A zone on the 1/3 target at 10 yards and I cannot do all A zone hits on a full size target at 30 yards.

Just a little something new to try.......

[Detlef]

yes, it's the same *area* when the target is small compared with the distance. A barn door at 20" is not the same *area* as a 1/2 size barn door at 10" ....

But you are right, the 30 y full target is more difficult a shot than the 1/3 size target at 10, and it has to do with visual focus. Your focus varies a lot more between front sight and target at 30 y....

--Detlef

(Edited by Detlef at 7:06 pm on Jan. 29, 2002)

[Nik Habicht]

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Quote: from toojon on 6:31 pm on Jan. 29, 2002

This started with a site offering 1/3 size ISPC targets as a free download.

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And where perchance did you find this site? Sounds like just the ticket for my basement...... unless I buy that mini target kit.....

[EricW]

The relative area of the target varies with the square of distance.  So a full size target at 30 yards is 9 times "harder" to hit than the same target at 10 yards.  So for the same difficulty, you'd need a 1/9 scale target at 10 yd.  I think putting the 1/3 scale target at 15 yards gives you the same difficulty factor as the full size at 30, but I need to check my math better.  I'll edit the post if my result is different.

Eric

(Edited by EricW at 12:07 am on Jan. 30, 2002)

[DogmaDog]

A 1/3 size IPSC target at 10 yards subsumes the same angle (has the same angular size) as a full size target at 30 yards.  

Points already made are valid:  Eye focus must shift more to acquire and hit a 30 yard target.  

Bullet holes are relatively larger on the small target, so breaking into the next scoring ring is more likely.

Also, there is greater bullet dispersion at 30 yards...your group size (generally) opens up at greater than a linear rate, so group size at 30 yards is > 3 times the group size at 10 yards.

I've shot in rifle matches where the range lacks a 600 yard line, and uses a 500 yard reduced target.  The target is actually smaller than 5/6 of the 600 yard size, to account for wind and other factors that have non-linear effects.

Semper Fi,

DogmaDog

[vluc]

I believe that there is a formula for size and distance on this thread:

http://www.brianenos.com/cgi-bin/ikonboard...=8&topic=27

(Edited by vluc at 4:54 pm on April 26, 2002)