Does somebody know where to download some sample 'target thermometers' ?
This has nothing to do with measuring temperature but the paper cart looks like a thermometer with a zero at (for instance) 100 meters and known impacts at 200,300,400,500 etc meters for a given bullet & speed.
This is used to sight in a rifle at a 100 meter range for 600 meter (for instance).

DCRA (Dominion of Canada Rifle Association) used to sell them for use with the .308 cartridge. Don't know if they still do, but I would suspect they do.

The DCRA shooters used them to make sure their rear iron sight was moving absolutely verticle when they cranked it up for the various distances at which they competed. If it is not verticle, then each increase in distance [elevation] also causes some change in windage. (It is effectively a built-in "Cant".)

The target has a single heavy line from bottom to top, with "hash marks" for the various ranges normally shot there (300, 400, 500, 600, 800, 900, 1,000 yards). Since the conversion to metric, I would assume they changed those markings to be right for 300, 400, 500, 600, 800, and 900 meters.

Anyway to use them for checking rear sight, hang the target with a "plumb-bob" to make certain the vertical line on the target is truly still vertical when the target is posted.

First sight in at juncture of bottom hash mark and the vertical line with at least a 3-shot group. Then crank on elevation for the next distance (next hash mark) up. Shoot a 3-shot group. Higher group should still be exactly centered on vertical line. Repeat for each of the distances on the target. Groups should all stay centered on the line.

Same target should also work to make sure the vertical crosshair in a rifle scope is actually vertical, too.

(N.B.: All groups are fired at a distance less than 50 yards...I just can't remember exactly what that distance is.)

I now have such a sample.
"7.62 RG Ammo"
left is 144 grain, right 155 grain.
They told me the shooting distance was 60 yards.
It indicates 300,500,600,900,1000 yards.
300 yards is the Zero, big black circle.

I now want to produce some for my own ammo like
the 6BR, 7mm-08 and 7.65 Arg Mauser.
(have bulletweight, BC & speed of bullet)

Glad to see you found one. Your's must be a Brit NRA-designed version of that target, seeing as it is for RG ammo (Radway Green?) Do you know its vintage? I wasn't aware the Brits hadn't yet converted to metric ranges....

I tried to make a scan of it, but it was on A3 paper, so I 'glued' the two pieces together.
Here's what I got :

http://users.telenet.be/schietsport/762RGThermo.jpg

Brits are still in yards.