Hmmm is it possible the springs are not sitting 100% flush? If they were to buckle a bit, it could cause the bolt to ride the guide oring in an uneven fashion. That might wear the orings down quick. Of course changing the oring out would solve the problem for a while, until you wore the new one down again.
Anyone have a pic of the spring? Is it ground down to sit perfectly flat on the ends? Do the coils finish at the same spot on both ends? No demon here.....just thinking about what could cause these #11 guide oring failures.
ETEK 3LT, with 14" critical .680 barrel and cure 3 + bolt F/S
DM12 red with matching Boomy F/s