I think the translation is a bit loose. My google translate burped out 'small predators', I think it may be that the German word is not a direct match for 'predator', and that might be similar to that for vermin i.e. things that prey on human foodstuffs etc rather than meat-eaters like snakes and lions, so I think it might be that the Germans were suggesting that it could kill rats and mice at 55 yards. The German for main-spring in an airgun translates to 'feather'!