Already for several years stiffness measuring devices are used for the clothing controls in the shooting sports. They exist of a movably mounted measuring cylinder with a diameter of 60 mm. A measuring plate with a diameter of 20 mm and a weight of 1000 g presses these.
The material of the interposed shooting clothes (with the jacket shows the outside and the trousers the inside upwards), should allow to press at least 3 mm down. It should be measured in several areas of the clothes pieces, see drawings.

Remark: The drawings are image quotations from the rules of the ISSF.

The photo on the right shows an implementation of these measuring instruments with temporary tabletop. Because the devices are delivered without table, the organizer must built it itself. In the rules the tables are liable to the following demands:

Quotation from the rules of the ISSF:
1. Inlet the machine into a table (approx. 1.2 m across x 0.85 m deep, table height at a comfortable working height) or other smooth work surface sufficiently large enough to be capable of supporting the largest shooting jacket or pair of trousers. The measuring cylinder “A” must be level with the work surface.

Photo below on the left: the part of the measuring instrument which is lowered with a weight of 1000 g lies openly.

Photo below on the right: because the shooting trousers are quite stiff, they do not remain lying simply open, but the trousers opening must be held on almost always. On the picture one can recognise that a part of the trousers opening touches the open recumbent part of the measuring instrument.
The measuring cylinder is thereby braked and may indicates a wrong result.

The photos below show the situation with trousers:
Upper row, left outside: The photo shows the upper part of trousers lying on a table. It reveals to themselves the natural body form with wider bottom and narrower waist, because the waistband stands up. If the trouser legs (against the ISSF rule) hang down from the table, the effect of the raise is strengthened.
Upper row ,middle: One sees that the waistband of the trousers lying under the measuring instrument also bends upward.
Lower row: Also a weight of 250 g or in the other case of 600 g do not get to press the waist to the table.
Upper row on the right: Only if one raises the trouser legs or puts them up, the trousers flip to the back, so that the waistband lies flat.

Only in this position, pants should be measured.

The photos below make the situation clear:
On the left outside: The photo shows a jacket lying on a table from the bottom seen. Although in the shoulder area lie weights , the jacket is not level, but lies very wavy.

On the left inside: The following photo shows a closer view. Although a weight of 600 g lies on the left shoulder part, the jacket stands off from the tabletop some cm.
On the right inside: A look from the lower egde of the jacket. The weight of 250 g is not enough to press the jacket on the table.
On the right outside: Also on top in the shoulder, 250 g are not enough to press the soft leather down.

Only fabric of the roll or true skins of the trader lie level, so 2-dimensional. Tailors try hard with well made patterns to give a perfect fitting 3-dimensional form to it.
The fabrics or the leather are cut in form and then sewn together. Then the jackets sewn from it and trousers cannot lie level any more.
If one tries to put down parts of it level, tensions always originate. These pull up the material at neighbouring places.

From the above pictures is to be seen that always a certain pressure must be applied to bring the measuring parts under the stiffness measuring instrument.
The stiffness measuring instrument works with a weight of 1000 g which should press the material at least 3 mm deep in the measuring cylinder down.

How much from the weight of 1000 g really work on the stiffness measurement? And how much of it are already used to bring the parts just on the level of the measuring cylinder?

If all parts to be measured of a shooting jacket exist of exactly the same material, with every cut part other measuring results come out,

CAN ONE CALL THEN THE MEASURING INSTRUMENT PRECISE?