I have a friend that is a "rocket scientist" (Lawrence Livermore Labs). He has a causal interest in shooting and hit me with this exact arguement. He stated that the bedding, action, rings and scope tube should all be the same to avoid "thermal unrest" (his words not mine). He explained the flexing issues and after examining a model 700, he felt the open action top was a problem for true precison. He then looked at my Surgeon RSR with the smaller port and steel rail and wondered why anyone would ever bother to use a 700 action and go for extreme precison. He saved the best for last though. After going through all the minuta he said that is was all out the window as soon as you left a test tunnel and missed a 2mph wind call.
Also just thinking out loud...how do we confirm that the bedding block is offsetting the flex from the tube? What if they were both moving in the same directions, wouldnt that double the potential movment from thermal expansion? I have no dog in this fight, I run everything from McMillan
, HS light varmint and the Mcree stocks.
Speaking of the Mcree, why not just go that route or something similiar and get away from bedding entirely. I know its not pretty but performance wins over cosmetics for LR shooting.
Al Harral has done a variety of test on thermal expansion and his page is worth a look. http://varmintal.com/ashot.htm#Scope_Base