The O-rings are in a simple stack, the OD is a snug fit in the tube (ie no play).... They are not fastened together in any way, they just sit in a stack up against the back of the valve.... The total valve lift we are dealing with without any buffer is about 0.050"-0.060" at the beginning of the string to 0.100"-0.120" at the end.... When I measured how far the O-ring stack could flex on hammer impact (in this gun), I got about 0.060" for a 4 high stack of 70 Durometer.... and that is with FULL hammer impact, ie after the O-ring stack flexes that far, there is no energy left to open the valve.... In other words, each O-ring distorts from a 0.103" circular cross section to flatten by about 0.015" or so, although the top one may in fact distort more and the one touching the valve less.... I haven't seen any indication that the O-rings are "getting out of place", I would think that would turn up as large jumps in velocity.... I would think that if one got wildly out of place, it would remain so, and turn up on disassembly.... Nor have I heard/read any reports of that happening, although I would agree that is is theoretically possible.... When you go to remove them, you have to hook them and pull them out of the tube....

Bob