Hi Rich, when the spring takes a set, and continually does so, (depends on quality of spring material, and cycles of use) it gradually becomes larger in overall coil OD (and shorter in length)... And, it starts dragging on the magazine shell at the worst times! Basically at full compression, it becomes a sort of brake on the mag shell from dragging in the spring relief area with this now, overly expanded OD!!...Almost all springs are manufactured to spec, and take a set, gradually, to out of spec, or failure from fatigue... I designed a P.08 magazine replacement spring of the best material, to take a permanent (or nearly so) set just into spec...
... Strong and never drag from setting?? It seems as if they are, "bullet proof!"...
..... Sorry for the lame pun!... best to all, til...lat'r....GT
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