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douglaswlloyd
October 8, 2007, 06:21 PM
Hello,

I'm new to this forum, but have shot CMP matches for about 5 years.

I would like to do some realistic dry fire practice during this winter, but cannot manage the 200 yard distance between me and the target on my property.

My question is this: How much smaller should the standard 200yd target be to present the same sight picture at 100 yards? How about other distances?

If someone has already worked this out or there is a conversion chart please forward me this.

thanks,
Doug

Howard Roark
October 8, 2007, 11:12 PM
All you need to do is print out a series of periods of progressivly larger sizes untill it looks right for the distance you have to dry fire.
. . . . .
Make the next line bigger and so on.

Here is a link to reduced targets in pdf.
http://ray-vin.com/frtech.htm

You can dry fire at any distance. 10' is as good as 200 yards if the target size is correct.

Tn Tom
October 8, 2007, 11:55 PM
Mr Doug,
I thought sure I had the SR targets saved in PDF format but dang if I can find them.
On page 14 of the NRA Rulebook you find all the dimensions if you want to draw your own. In the mean time Ill find the site for the downloads.
Tom

try this its got what your looking for
http://dotclue.org/targets

cdrt
October 9, 2007, 10:30 AM
You might try using the 50 yard slow fire target (B6) that is used in Bullseye (NRA Conventional Pistol) at 100 yards. I've used it with my M1 and it takes the same sight elevation that I use for the std 200 yard target.

ocabj
October 9, 2007, 12:52 PM
The size of the aiming black on an SR target (200 yard target High Power) is 13 inches. You can figure out the correct reduced size of a target for a specific distance using simple math.

The way you are supposed to calculate a reduced target is using MOA, or minutes of angle.

The formula that correlates the relationship of MOA to the size/length/diameter of a given target is:

http://www.ocabj.net/gallery2/d/3198-1/moa_equation_1.gif

One common example explaining MOA in terms of inches is the size of 1MOA at 100 yards, such that 1MOA / 60 is the angle in degrees:

http://www.ocabj.net/gallery2/d/3202-1/moa_equation_2.gif

So, in order to find the size of the aiming black on the SR target, you simply adjust the formula used to calculate the size of a target based on a given MOA to instead find the unknown, which in this case is MOA.

http://www.ocabj.net/gallery2/d/3215-2/moa_equation_4.gif

Now that we know 13" at 200 yards is 6.207036036 MOA you can use that value to create the appropriate sized aiming black for the distance you will be practing your dry firing at. To test this value, we can cross check it against 100 yards (since the reduced SR target for 100 yards has an aiming black of 6.5 inches; 200 yard aiming black of 13 inches divided by 2).

http://www.ocabj.net/gallery2/d/3218-2/moa_equation_5.gif

So 6.207036036 MOA is correct.

ocabj
October 9, 2007, 03:30 PM
So as a follow up, let's say you are going to practice inside the house and you are going to stand 20 feet away from the wall where you will put up a black aiming dot.

Since you know the size of the aiming black must be 6.207036036 MOA for whatever distance you are from the target, simply plug that into the equation using 20 feet as your distance:

tan (6.207036036 / 60) * 20 feet * 12 (inches per foot) = .4333333333~ inches

Thus, for the proper size target at 20 feet away, the black circle should be .4333333333~ inches.

Simple.

douglaswlloyd
October 9, 2007, 11:02 PM
Awesome! This is just what I needed. Thanks Jonathon!

This article ought to be written up as a permanent tip and stored somewhere handy for other novice shooters.

Doug