Roy,
Torque values will vary from smith to smith. Some get very critical about this. I generally do not. I screw down a receiver until it bottoms out, work it back and forth several times to really work in the assembly thread lube and then give it a good torque and leave it.
I used to measure the barrel torque and have heard numbers anywhere from 80 ft/lbs to 40 ft/lbs is correct. TO he honest, the better the thread fit, the less torque you really need to keep them in place.
Things to consider however are, what velocity is your chambering likely to be getting, what bullet weight are you using, what twist are you using and such.
The lighter the bullets and slower the twist the less stress there is placed on the threads. If your driving a really heavy bullet in a fast twist barrel to high velocity, there will obviously be more stress on the thread torque level to keep that barrel in place.
All that said, I would say I probably torque my barrels to around 40 to 50 ft/lbs on average. Just a good pull on the receiver wrench.
Some BR shooters use much less then this and still have no problems with barrels turning out but comparing a 22 PPC with a 52 gr match bullet to a 338 AM with a 300 gr pill are totally different stories.
Critical thing is thread fit and even square, 100% contact on your barrel shoulder to the receiver or recoil lug. If you have that, you will need much less torque to keep a barrel in place.
The reason some Rem 700 barrels are so **** tight is because the thread fit is so bad that they fill the space between the threads with a thread locking agent and it can at times be a real pain to break loose. Especially with that **** taper right from the receiver like Remington does. Not a problem though, there are ways around that!! /ubbthreads/images/graemlins/grin.gif
I have had two barrels that simply would not break loose no matter what I did, 15 minutes after the 5300 lb lathe got ahold of them the threads were clean and clear!!! /ubbthreads/images/graemlins/grin.gif
Also, some firearm companies have a sad way of indexing flutes or bring headspace into adjustment. That is by torquing the living hell out of a barreled receiver. This is simply poor machining and the WRONG way to do it.
You may be suprised to find out that Ruger rifles for me at least are by far the most consistant barrels to easily brake free. Winchesters are by far the worst in my opinion, Rems are in the middle of the pack.
Kirby Allen(50)