No, this 2004 letter specifies that the string with loops on its own, because it was designed to be used to modify a rifle to fire automatically, was a machinegun.
Three years later, in 2007 the ATF decided differently, "Upon further review, we have determined that the string by itself is not a machinegun..."
Three years later, in 2007 the ATF decided differently, "Upon further review, we have determined that the string by itself is not a machinegun..."
https://everydaynodaysoff.com/2010/01/25/shoestring-machine-...