Just as a data point of one, I have a LRH mini chassis that just won’t get the same level of precision as other LRH’s I own. Tried multiple barreled actions in the suspect stock. Tried multiple action screw torque values from 50 in-lbs front/45 back, to 90 and 90. Same hand loads. Take a barreled action from that stock and drop it into one of my other LRH’s and holes on target don’t lie. I did this with five barreled actions (2 defiance and 2 impacts, one Mac bros element), with barrels from Bartlein, Carbon 6 and Mullerworks chambered by very well known gunsmiths with very strong reputations nationally and definitely in competition shooting. It is repeatable and noticeable.
I have no real idea what the issue is with that stock. I suspect there is a straightness issue in the mini chassis layup, causing some small stress on the actions. The group sizes consistently reflected tighter groups in a different LRH, TCS, TS Customs KS1 and Foundation Gideon.
I think a careful bedding job would solve the problem, I just haven’t done it yet. Part of the attraction to the mini chassis is not being tied to one action, but I probably need to just bite the bullet and bed it.