Man that wood stock can sure be a problem living somewhere with all that humidity you guys deal with down there.
One way to combat dealing with your groups going to crap after your barrel heats up is having the gun cryoed (droped in a liquid nitrogen tank at about -430 degrees) but to be honest I dont think I would do it unless I droped the wood stock,though having the work you had done to it will do wonders as well as getting some trigger work done,but if you are shooting a lot and doing some long shooting having the rifle cryoed is a big deal thats for sure as the barrle heating up will no longer affect your zero no matter how hot it gets.