Unfortunately I don't have a link to that image, but here's a link to a blunt arrow that was made by a Mansi hunter in the late 19th century. It was bought by Uuno Sirelius in 1898.
https://finna.fi/Record/museovirasto.71A546CE6605423DD86BCC292CA02B42?imgid=1
The translation for the "usage" section is:
"Used for squirrel hunting. The club-like head is made from heavy and dense curly birch and it will stun a squirrel or a sable when it hits its head. The hunter can then finish off the animal without damaging its valuable pelt. The arrow type is very old because furs have always been used for clothes so intact pelts were desired. During Sirelius's time the Mansi paid their taxes with squirrel and sable pelts."
The measurements are: length 88 cm, diameter of the head 5 cm.
The photos of blunt crossbow bolts that are in the Finnish National Museum's collections apparently have not been digitized to Finna, yet. They were used to hunt squirrels and mustelids in Karelia up to the 19th century. The crossbows that Karelians used had wooden prods so they were nowhere close in strength to medieval war crossbows.
The technique for squirrel hunting was that it was always done with a dog. When the dog noticed a squirrel, it started to bark at it. This made the squirrel to circle to the other side of the tree trunk and freeze in place, which made it easy target for the hunter.