5m scaled down targets

[gimgim]

For space reasons, I mostly practice in the garage, with 5m targets I get here:
https://www.ebay.com/itm/106T-5-Meters- ... 2097271052

I have a few questions that perhaps people here can answer:

1) These targets are slightly smaller than the pdf versions I have seen online (printed 1:1, laser printer). Diameter of the 1 ring is 7.8cm and diameter of 7 ring is 3cm (50% of the 10m targets). Which ones are correct?

2) Is there a rule of thumb I can use to correct the scores and normalize to a 10m target? (I expect the score at 5m to be higher)

3) Is there any source of these targets in the US? Kruger doesn't have them, these are specially printed fro Cibles Canada and shipping can be expensive if you only buy a few.

[wasatch]

For reduced distance practice i calculated the diameter of the black at my reduced range of 7m which is 42mm.
At 5m the diameter of the black will be 30mm (5m/10m x 59.5mm = ~30mm).
Then i cut a 42mm diameter hole in a target and use it as a template to make black discs on the backs of targets using a fat sharpie.

Luckily for scoring a 7m reduced size target has been posted on TT here: http://www.targettalk.org/images/Attach ... Target.pdf

I used it to create the attached pdf which I had printed on a transparency to overlay on the shot target for scoring. The pic shows the general idea (the pic is 7 stacked photos, 6 shot targets and 1 of the scoring rings).

At 5m use the info in this thread to calculate the adjusted scoring ring sizes (cause while the target can scale the pellet doesn't): http://www.targettalk.org/viewtopic.php?t=29348

Here's a thread w/ scaled 5m target pdfs: https://www.gatewaytoairguns.org/GTA/in ... ic=16628.0
And another 5m thread: http://www.targettalk.org/viewtopic.php?t=11392
The other attached pdf has many scaled targets.

[atomicgale]

At 5-meters: Use air rifle target (black = 30.5mm actual).

Compared to "apparent" size of half-range pistol target ( black 59.5mm / 2 = 29.75mm)

Saves a whole lot of money.

[Ricardo]

You can also print a 10m target at 50% scale on the back of a target. It comes out really nice! Lots of ink used, though. A rifle target is best.

[Ramon OP]

I made a calculator for size (with the percentage to use in the printer) and height of target (Apparent height and real height are not the same, the farther you walk from the target the higher it looks to be)> https://www.olympicpistol.com/target-calculator.html

[gimgim]

Thanks, lots on info to digest!

[Gwhite]

I made a calculator for size (with the percentage to use in the printer) and height of target (Apparent height and real height are not the same, the farther you walk from the target the higher it looks to be)> https://www.olympicpistol.com/target-calculator.html

Looks nice! Does the calculator take into account a correction for the bullet/pellet diameter? I assume so, but it isn't clear.

[Ramon OP]

Looks nice! Does the calculator take into account a correction for the bullet/pellet diameter? I assume so, but it isn't clear.

I'm not sure I understand your question. I use them to train either not firing at all or dry firing.

If you shoot, the ballistics are not the same, and the bullet hole size will be bigger. You will not be able to count the points as if they where real, but depending on the distance you could maybe get an idea of grouping.

I have not used it with any projectile yet, but will do for 50m free pistol as my range is only 25m long.

[Gwhite]

It may be that the scaling is too extreme at 5m, because if you adjust so the score will be roughly correct, the black will be noticeably smaller. People just need to be aware that scores on a linearly scaled target without bullet size compensation will be overly optimistic.

As an example: To scale a 10m air pistol target with a 5.95 cm diameter black to 5m for 4.5 mm pellet diameter, shots that just touch the black at 10 meters will have their centers on a circle 5.95 cm + 0.45 cm = 6.4 cm in diameter. That scaled to 5m will be 3.2 cm in diameter. In order to have such a shot just touch the black on the reduced target, the black must be 3.2 cm - 0.45 cm = 2.75 cm in diameter. That means a simple linear scaled black would be 2.25 mm larger than a black that would produce the same score.

I have a Noptel electronic trainer that allows you to print out scaled targets, and I believe they take the bullet size into account. They may scale the target linearly, and adjust for the bullet size in the software. I use their 50 meter free pistol target scaled to 10 meters, and the scores it predicts are very close to what I shoot outdoors.

[gimgim]

> They may scale the target linearly, and adjust for the bullet size in the software

If you estimate the center of the shot, it should be quite easy to scale down the bullet as well.

What I have been doing so far is subtracting 20 points to the final score (for 60 shots).

The rationale is the following (I am not considering the 10 - 11mm diameter - and the math could use a second look :-) )

In a regular target, the circles are 8mm wide.
You score P if the center of the pellet lands between 2.25mm and 10.25mm to the right of the P+1 circle

In a 5m (50%) scaled target (4mm wide circles)
With a 50% scaled down pellet on a scaled down target, you score P if the center of the pellet lands between 1.125mm and 5.125mm to the right of the P+1 circle.

however, with a full size pellet, the score will be
P+1 when the center of the pellet lands between 1.125mm and 2.5mm to the right of the P+1 circle,
P when the center of the pellet lands between 2.5mm and 5.125mm to the right of the P+1 circle

The fraction of shots that are correctly scored on a 5m scaled target with regular size pellets is
(5.125 - 2.5) / (5.125 - 1.125) = 0.66 (66%)
and the fraction of shots that are overscored by 1 point is 34%

If this math is correct, a rule of thumb could be to subtract 20 or 21 points to the final score (60 * 0.34 = 20.4).
Makes sense?

Caveats: This works if the distribution of the pellets is uniform (like in my case :-) ). Once you start having very tight groups around the 10, the overscoring can be much higher than this.

[Ramon OP]

The main issue with taking into account the center of the shot (which is complicated by itself without an electronic target which already do it like this one https://www.olympicpistol.com/inband-ai ... et-review/) is that it does not take into account the angle at which you shoot, if you break your wrist lock, give a sudden move... It will never be a substitute.

Forget about the points, only compare targets at the same distance and try to adapt so that you can get some learning done :)

My work for Free Pistol at 25m is just shooting on figures or a small bullseye to have some kind of reference and then all I pay attention to is my sensations, posture, how I'm holding the gun, my process... internal stuff, nothing related to scores. I know that the grouping does not reflect the one of a real 50m range, but it helps me train.

[NukeMMC]

2) Is there a rule of thumb I can use to correct the scores and normalize to a 10m target? (I expect the score at 5m to be higher)

I wouldn't worry about scoring, especially on a reduced target, for practice. Your time may be better spent comparing your call to shot location and figuring out if/why there is a difference and group location/size and centering and shooting smaller groups.

[PirateJohn]

I made my own 5m targets on Adobe Illistrator. You need to remember that the pellets don't scale down so you have to take that into account. It's not as simple as just dividing the diameter by two.

To make the 10 ring, which is normally 11.5mm across, I added the diameter of a pellet, divided by two, then subtracted the diameter of a pellet. So my 10-ring was 3.5mm across. The black area ends up 27.5mm across.

[Grippy]

To make the 10 ring, which is normally 11.5mm across, I added the diameter of a pellet, divided by two, then subtracted the diameter of a pellet. So my 10-ring was 3.5mm across. The black area ends up 27.5mm across.

This is the correct procedure but it can be slightly simplified. For ring diameter x and pellet diameter d you get: (x+d)/2-d = x/2 + d/2 - d = x/2 - d/2. So it's simply halve the diameter minus 2.25mm.

However this should only be applied to the rings but not the black. Since you want that one to be visually the same and not scoring wise. So the 7 ring ends up slightly inside the black.

[PirateJohn]

This is the correct procedure but it can be slightly simplified. For ring diameter x and pellet diameter d you get: (x+d)/2-d = x/2 + d/2 - d = x/2 - d/2. So it's simply halve the diameter minus 2.25mm.

That simplification will work when halving the distance, but doing the extra step will work for any distance. So if you have 6 meters to work with and want to scale to that, you'll need the extra step.