Rimfire target ring scoring gauges for 5-shot groups:

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For newbies to scoring targets, (including me), I thought I would provide a review of scoring gauges for group ragged holes (as opposed to single shot mini bulls which are easily scored with plug gauges), based on what I have recently learned. Experienced match shooters will be well familiar with all of this, so your added advice is very welcome.

For newbs to match scoring, on quality target paper the bullet punches out a hole smaller than the bullet diameter, and pushes in petals of paper that will show a carbon smear ring. That outer carbon ring is the bullet diameter and is what marks the true hit edge. On poor quality paper that is too thin, the bullet can punch out a hole or make a tear larger than the bullet diameter. So, in both cases scoring gauges are needed for the details.

I recently started shooting aperture sights at 50m. So far, I have only shot only benchrest discipline (later I will try 3-P disciplines). Due to the size of the aiming bulls and size of the paper needed for aperture sights, its necessary to shoot 5-shots per bull. The standard ISSF 50m target has 4 bulls for record, 5 shots each for 50 max points, total 200 max points per sheet.

In benchrest with the fully supported rifle, the 50m 5-shot groups can be amazingly small if the wind is not too bad, causing ragged holes that blow out the paper along with the fine scoring rings in the 10 and X ring area. The .22 scoring plugs we all use and which all clubs have for single shot scoring, may not work accurately when there is a mess of a ragged group hole for those tiny ISSF 10 and X rings.

For example, photo 1 is a 50m target I shot yesterday that shows a 5-shot hole in that 10 and X ring area that would be difficult for a plug to score accurately. Some holes are easy, some not so easy. How did I determine the 49-4X score? In this case the 49 looks solid, but am I confident its not 3X or 2X?

Best_Target_49-4X.jpg

So I just bought two new (to me), scoring gauges I found online at Cibles: A magnifier viewer scoring device, and a simple transparent card overlay gauge. Problem solved! These work great!

One is a .17 and .22 rimfire caliber magnifier gauge (costs more), and one is a mixed caliber transparent card (inexpensive, buy a few).

Photo 2 below is the magnifier gauge. It contains 2 ring gauges: a single .17 caliber ring, and a .22 caliber double ring. The .22 gauge inner ring is to center the gauge on the smaller diameter punched-out hole. The outer ring is the true .22 diameter for indicating the hit edge for the carbon smear. See Photo 3 and 4 for examples.

Cibles_Scoring_Gauge_Magnifier.jpg

Photo 3 below is looking through magnifier at an example showing how the gauge clearly shows that the highlighted round cut the X-ring on the 50m ISSF target, so it scores 10-X. (Ignore the .17 caliber gauge ring). The reflection and blurriness around the sides looks bad in the photo but that is a camera effect of my cell phone snapshot. With your eye things are very clear.

Example_X-Ring_Cut.jpg

Photo 4 below shows looking through the magnifier at a close call for the highlighted round. Without a scoring gauge it can be an uncertain call. In this case I read the gauge to say no, the round did not cut the X-ring and score remains a 10, no X. The paper on that inner white ring is not physically cut, but the carbon smear could be there. But in this case the gauge appears to indicate no it was not touched by the round.

Example_X-Ring_Not_Cut.jpg

End of part 1. Please see the next post for the transparent gauge card and questions I have about how these work.
 

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Continued, part 2:

Photo 5 below shows the transparent gauge card, and I have some questions that you might be able to help me with.

Cibles_Scoring_Gauge_Card.jpg

The .22 ring (Canadian or International) is self-evident for aligning on the hole. But I have no idea what the "Skid gauges" are? It says ".22" but then it shows "7mm", but .22 is 5.5mm. There is a "CF/CP" of 11mm? These dimensions do not align with any rings on the 50m rimfire ISSF target that I could find, so I am guessing these skid gauges are for a different type of target? I realize there are many different official target types for calibers and distances for rifle and pistol.

However, I did find on the card 2 dimensions which are very useful for the 50m ISSF scoring, but these do not seem to make sense to me from how they are labeled on the gauge card.

Photo 6 below shows the space between the lines of the 7mm and 11mm Skid Gauges just happens to be almost exactly the space between the 9 and 10 ISSF rings. This is a zone on ISSF targets that gets blown out and can be difficult to score. I found that I could overlay these spaced lines to touch the 9 and 10 rings as shown, and then place the magnifying gauge over top to then see if the rings on the magnifier cut the card lines for a shot hole.

Card_Gauge_7mm_11mm.jpg

Photo 7 below shows the card's double ring labelled "CF/CP", and its outer ring just happens to align almost perfectly with the ISSF 10 ring. The inner ring does not align with anything I could find.

Card_Gauge_CF_CP_10_Ring.jpg

When the ISSF paper 10 ring is mostly blown out, this CF/CP outer ring can be placed on this area and the magnifying gauge, or another card gauge could be placed over top to determine if the 10 ring had been cut by the round.

Any advice is welcome, thanks!
 

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The International CF/PC double rings are for scoring centre fire ISSF targets. If a competitor is shooting a .32 caliber pistol in the centre fire competition it is scored as a .38 caliber.
 
Potashminer, thank you for posting that "NSRA SCORERS COURSE" document. Excellent! That is a gold mine of a document for how to score, and the various gauges available. Downloaded for my library.

This document explains many of the questions I had (like skid gauges), and now I know what the decimal scoring tools are for and how the Vernier scales work on the rings. I saw the decimal gauges for sale online but never understood what they were or how to use them. Now I know.

I was never trained in any of this information. My local range does not have anyone running scoring matches with aperture sights and ISSF official targets. I am on my own just practicing with no where to compete. I guess I will have to organize a new club if I want to compete in aperture shooting.

At my range for rimfire we only have benchrest matches using high magnification benchrest scopes, and shoot on single shot mini bulls (25 to a target sheet) that we score with plugs. Multi-hole targets scoring was always a mystery to me.

Thanks HammerliSP20 for that info on the other rings.
 
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What diameter is the aiming black and where did you get the targets? I’m guessing the diameter to be somewhere around 3-4” for 50M. I’m surprised they allow 5 shots per target as marking would be difficult.
 
What diameter is the aiming black and where did you get the targets? I’m guessing the diameter to be somewhere around 3-4” for 50M. I’m surprised they allow 5 shots per target as marking would be difficult.

ISSF smallbore 50m target black aiming bull is 112.4 mm. The full target spec is on page 232 of the ISSF General Technical Rules document, downloadable from ISSF website, link:
https://www.issf-sports.org/theissf/rules_and_regulations/general_technical_rules.ashx

I got the smallbore "50m Match Rifle" targets (250 pack) that meets the official ISSF specs, from the Shooting Federation of Canada (SFC), link:
https://sfc.gilmoreglobal.com/en/product/5908173f-d26d-467c-8a9b-d1f6ab25af15

I got repair centers, "CCT Center Patches for #151", which are also official ISSF specs, from from Cibles targets, link:
http://www.targets.ca/products/targets

The SFC target sheets are large (16.5" x 26"). They have 4 bulls for record and 2 sighters.

So large that they won't fit the small target frame backers that my local range uses (They built our frames 2' x 2' with a frame, so only about 21" x 21" useable space), so I have to cut the 2 sighters off the top of the 26" target sheet. That is why I tape the repair center into the middle of the 4 remaining targets for record, as a sighter.

Multiple rounds (5 per bull) are needed per bull in the 50m target sheets because otherwise you would be running downrange back and forth to change targets many times for one match of 20 rounds (200, 50 points per 4 bulls), unless your range had large backing board frames for multiple sheets per shooter. Something like 2 rounds per bull would require 10 bulls, which is 2 large sheets if you use 2 of the sighters for record. Do-able on a range if you were to build the target frame backers large enough. But you woudl be shooting 2 sheets, and cost wise that's more expensive.

On the SFC targets page, they show the 20 yard and 25m smallbore target sheets (18.75" x 15") with 10 bulls for record, plus 2 sighters (3 rows of 4 bulls) that all fit on the one sheet because the bulls are smaller, so less area is needed for the white space. I have never shot those, but I am guessing for a 200 point match of 20 rounds, that is only 2 rounds per bull, making scoring much easier.
 
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