Bone Knife

doesn't create a sash on the player

These don't lose durability when used on dead animals and humans, so it's a good idea to take one of these with you when you go hunting.

Using bone knives to farm barrels is a very cheap and effective use for bones because they currently do not have many other uses.

You can actually exercise with a bone knife to make plays with it in combat (low geared players, nakeds, roleplayers etc). The combat style would be: jumping around the victim, slashing rapidly, making "jump blows".. basically, like a ninja.
The low amount of damage is able to be compensated by such a combat style, and the attack rate, surprise element, and the rush of the attack felt by your opponent (who doesn't know where to run, and how fast). After some exercise, it's pretty easy to kill a bow guy with it. You can place down 3 or 4 slashes every time they slide an arrow up.

Farming overview tl;dr:

Bone knife is #9 for barrel farming, and not recommended for roadsigns due to low durability.
However, due to the cheap cost, it can be much better than a rock.
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Soft Barrel Toplist:

#1 - 0.32s › Sword, Icepick, Salvaged Axe
#2 - 0.72s › Mace
#3 - 0.77s › Longsword, Cleaver
#4 - 0.85s › Combat Knife
#5 - 1.05s › Hatchet
#6 - 1.20s › Salvaged Hammer
#7 - 1.28s › Machete
#8 - 1.63s › Paddle
#9 - 1.70s › Bone Knife
#9 - 1.92s › Pickaxe
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Hard Barrel Toplist:

#1 - 0.77s › Longsword, Cleaver
#2 - 0.85s › Combat Knife
#3 - 1.20s › Salvaged Hammer
#4 - 1.28s › Machete
#5 - 1.55s › Sword, Icepick, Salvaged Axe
#6 - 1.63s › Paddle
#7 - 1.82s › Bone Knife
#8 - 1.92s › Pickaxe
#9 - 1.95s › Hatchet
#10- 2.12s › Bone Knife
#11- 2.73s › Mace
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Barrel Average TTK Toplist:

#1 - 0.77s › Longsword, Cleaver
#2 - 0.85s › Combat Knife
#3 - 0.93s › Sword, Icepick, Salvaged Axe
#4 - 1.20s › Salvaged Hammer
#5 - 1.28s › Machete
#6 - 1.50s › Hatchet
#7 - 1.63s › Paddle
#8 - 1.72s › Mace
#9 - 1.92s › Pickaxe, Bone Knife
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Roadsigns Toplist:

#1 - 2.77s › Mace
#2 - 3.20s › Salvaged Hammer
#3 - 4.05s › Sword
#4 - 4.13s › Paddle
#5 - 4.62s › Hatchet
#6 - 4.75s › Longsword
#7 - 5.22s › Icepick, Salvaged Axe
#8 - 5.38s › Machete
#9 - 6.73s › Cleaver
#10- 9.43s › Pickaxe
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Credit to Tamura77, loopuleasa

Excellent for breaking barrels, breaking bags during a raid, or breaking a soft side stone wall (requires many of them). Since it's low cost for 30 bone, it's relatively cheap to make for eco raiding.