Devildoc,
You need to reread my post. I never said that a new match grade barrel would not likely improve accuracy.
What I said is that there is a decent chance that there would still be consistancy and accuracy issues by just screwing on a new barrel. Let me explain why. A factory rifle is generally finickier then a custom rifle, why? Because machining quality is often very poor in many area:
-Poor bolt lug contact
-out of square bolt lug supports
-out of square bolt face
-out of square receiver face
-inconsistant recoil lug thickness
-out of axial alignment receiver threads
-loose receiver/barrel thread fit
-out of axial alignment chamber/throat
-off axis crown
All of these lead up to many things we see from factory rifles, including poor consistancy, poor accuracy, mystery fliers, etc.....
So lets pull the factory barrel and machine up a quality match grade barrel, with a quality machined chamber. AT this point, the barrel will be a shooter, BUT, now lets screw it onto a receiver that has out of axial alignment receiver threads onto a receiver face that is out of square as well.
When you torque the barrel down, even if you use a match grade recoil lug that is consistant in thickness, because of the out of axis receiver threads, when you tighten the barrel down, one side of the barrel shoulder will contact first and when you fully torque the barrel down, the barrel will flex at the shank until the barrel shoulder is solidly supported by the recoil lug with is supported by the out of square receiver face.
You just took a quality, stress relieved match grade barrel and imposed a hell of a stress into it because of this flexing to adhear to the receivers flaws.....
Stress will result in many potential problems on target. Ranging from fliers to stringing to walking groups. As the barrels heat up, this stress will change its results on paper. This is one reason many factory barrels are very inconsistant or have mystery fliers.
we have not even fired the rifle yet and we already have a stress in the rifle. Now lets look at what happens to the rifle when its fired.
When you touch a round off, you will have 60 to 65,000 psi slaming against the bolt face. This compresses the bolt until the uneven lugs contact one lug, then more compression will occur as the pressure builds and the bolt is flexed until it is pushed back and stopped by the on baring recoil lug. Again, flexing and stressing occurs when firing. This can lead to consistancy problems again.
Now lets look at the bolt face. Slam it with 65K PSI and the taper on the bolt face WILL act as an inclined surface as will the uneven bolt lugs. The bolt will be forced in the direction of the incline on the bolt face. It may also be driven in another direction because of the unsupported bolt lug contacts. This mainly results in fliers more then anything.
These conditions also worsen on average if the bolt is preloaded. It also increases on average with the larger the case head size is as well as the increase in chamber pressure.
This is often why a rifle with an unsupported bolt lug will shoot well at lower pressures but go to hell at higher pressure.
Will the rifle shoot better then the factory, likely yes, BUT, why spend X amount to get "Better but likely still some issues" when you could spend a bit more and get "Solid consistant performance".
Now I am not saying a fully accurized receiver based rifle will shoot every load into bug holes. BUT, it will shoot a much larger range of loads much better then a rifle that has not been trued.
As far as taking the barrel off and doing the accurizing afterward if the rifle does not shoot, well to some degree that is true, you could do that. But remember to properly accurize a receiver, it ALL has to be done. That means that the receiver threads will need to be single point cut which will increase their diameter. Which will mean existing barrel threads will not fit. You can cut the old threads off and refit the rifle but this is pretty much a complete new barrel fitting job.
Also, some barrel contours will not allow this because their barrel shanks are not long enough. some will some will not.
My comments and opinions, if your going to spend the money, why not spend a bit more and do it all and do it right from the start?
Again, I am not saying a barrel replacement will make the rifle shoot better, but better is not good enough for me. Better could still mean average......
That is my only point. See how the factory rifle shoots, if you can not get it to do what you want, there are some minor tricks that can be tried, if those do not work then if you decide to do more involved surgery, I would recommend doing it all and doing it right from the start just to save time, money and headaches, thats all.
Again, there was no flame intended toward your post, none at all, just offering my opinion as well.