Just to start this off I had to do all the testing at the mercy of mother nature there are going to be a difference in the weather ect. I bought a Winchester Model 70 Extreme weather a month or so ago. I got time to reload for it so I decided to do a little experment with it and move the bullet back farther by .005 every time. I got my reverence point with a Hornady O.A.L gauge and modified case. I decided to use 165 grain Nosler partitions, because I got a ton of them from shooters pro shop as seconds. The powder I used was IMR-4350, because that is what alot of people use for the old 06.
A little about the rifle. It is a plan Jane Winchester model 70 with talley rings and a VX3 2.5x8x36. When I got it home I gave it a good cleaning and used JB bore paste and ran a patch though 100 Times. I did adjust the trigger down as far as the factory trigger would let me. I torqued the front screw to 35 Inch Pound and the back one to 25 inch pounds. That is all that I have do so far to the rifle itself. I did clean it after every depth string with whip out till I got no blue or black on the first patch.
Brass prep was full sizeing new Winchester brass was a RCBS die. Trimmed them all to the same lenght and put them in a tumbler over night. The number you see on the side of the groups is grains of powder.
All targets where set at a 100 Yards with my range finder
My first day out at the range I was shooting with the bullet .015 off the lands. It was 5 degrees out and just a light wind. Not even enough to worry about. As you can see my best group was 55 grains of powder.
My next time out the range I moved the bullet to .020 off the lands and it was about 5 degrees again. This gave me my best group at 56 grains of powder. It shot right around .025. no wind