I recently read a post on this forum (or possably another one) where someone described a good technique for determining the best distance from seating the bullet off the lands. Basically, they said to take the bullet and powder you plan on working with and load it at the minimum recomended load. I believe he said start with the bullet .005 off the lands, then decrease the length until you find the group that shoots the best. When you have done that then start working increasing the powder until you achieved your desired results.
Do these numbers sound right to you guys...starting at .005 and working closer? Would there be any reason to start out farther or go out farther?
Thanks 280fan (my favorite cartridge as well). My numbers where way off, I should have said adjust by increments of .002 to .005, not that actual distance from the lands. I'm guessing the berger method will work with any bullet brand?
IMO you are still a decimal place off. Certainly it is OK to start at .005" off the lands but you will not see any significant change in group size when moving only .002" at a time unless you do a LOT of shooting. A more normal change in seating depth when looking for a seating depth would be .02" at a time. For instance .005" off, then .025" off, .045" off etc. Or at least vary it by .01" at a time.
Many bullets, especially the Barnes copper bullets, need to be started at .05" off and never get closer than .03" off. You will have a hard time regulating the seating depth to have a variance of less than .005" from bullet to bullet, much less .002".
IME when you get closer to the lands than .02" then you need to get absolute control of seating depth by consistant inside neck dimensions and bullet grip and by using a very good competition seater. I have yet to find a rifle where you could not find a good load by starting at .02" off and then finding the powder and powder weight the rifle prefers. Some rifles like Weatherby's and RUM's can be very accurate even when seated .275" off the lands.
If you can read this, thank a teacher.......if you are reading this in English, thank a soldier.
Seating at or into the lands, or even close, is a BR techique. But their rifles and their cases and their bullets are different from ours, so are the techniques needed. Attempts to use BR methods for our stuff is a mistake.
The BR concept of seating close has been repeated so often it has taken on a "conventional wisdom" life of its own but is badly misapplied for the rest of us. It's primary purpose was/is to retard bullet movement and improve ignition/burn with softly held bullets, but common "logic" got around to saying it helped center bullets into the bore. There is no data I'm aware of to support that to be true in our loosely chambered store bought rifles. So, I wish we could drive a stake in that idea's heart and get rid of it completly, 'cause it's NOT true for factory rifles - or very rarely so - and it's not needed with our high bullet seating tension!