Sitelite repeatability

I cannot get my Site Lite boresighter to repeat a scope setting. If I get an alignment set up, pull the spud from the bore and re-insert it, the alignment is off different amounts in different directions every time the spud is re-inserted, no matter the caliber or rifle.

Any help would be appreciated...

That piece has o-rings to keep it set in barrel?...
Chance one is missing...or maybe flattened on a side causing your problem.....
Maybe try some hard plastic rings on it rather than rubber....

entire unit is brand new, nothing missing. hard plastic rings won't flex to fit the locating grooves.

Mark it so installing in same position every time. David