I think that there needs to be an order of operations that is applied when one is trying to improve the accuracy of a factory rifle. At or near the top of the list should be proper bedding. Probably the next thing should be attention to the trigger. It is hard to shoot small consistently with a heavy trigger. Another thing that is often neglected is the way that it is supported while being shot. I see a lot of rigs that I guarantee will open groups and mask any potential accuracy improvement. Similarly, there needs to be some way to see what the wind is doing so that errant shots that come from the wind are not mistaken for load or rifle handling issues. As far as concentricity improvement goes, if you are stuck with a one piece FL die, using a two step process that involves sizing without the expander ball, and then using an expander die and mandrel to expand (lubed) necks will yield noticeably straighter brass. It is common to observe shooters that think that they can simply ignore some of the important factors for improving accuracy, and only work with the details that they are attracted to. As far as the need to true an action before accuracy improvement is attempted, that is simply not the case. In years back, I was able to achieve significant improvements in the accuracy of factory rifles by doing the things that I described above. While they would not have been competitive in a benchrest match, they would suffice for any varminting task with room to spare. Of course I checked lug contact, and did a little remedial lapping if I thought it necessary, but I do not consider that to be truing of an action. To me, that requires the skillful use of a lathe. I would caution anyone that he should do some serious reading before lapping action lugs. There are some issues involved that may not be entirely obvious to some.
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