Dewey;
I have springs on items from the 1850's thru 1870's (Not gun related) which are I believe called convolute springs. These springs are wound in a cone shape from flat stock much like a clock spring. They however work by compression & not by winding up as in a clock spring. So, what action would you call them, I see absolutely no evidence of torsional movement as they are compressed & this should show on the wide, thin cross section if it were present.

Miller/TN
I Didn't Say Everything I Said, Yogi Berra