I tried Newberry's OCW method for the first time several weeks ago on my .308. I loaded a total of 21 rounds to shoot 7 3 shot groups, round robin style at 100 yards. Components were Black Hills brass, recently cleaned and annealed, 178 AMAXs, and Varget. There were two possible charge weights that resulted, but I chose to use 45 grains of Varget, as I thought the higher charge may give me some issues when the weather heats up. I loaded up a box at 45 grains and seated them to 2.80 COAL, but then they sat for a while as I was doing some work to the gun. I finally got my new stock and got the recoil lug bedded last week, so I headed to the range to zero and test the rounds.
This was the first 4 shot group. I was pretty disappointed as the OCW groups had all been <.4 inches at 100. Then, as I was putting the spent brass back in the box I noticed that one of the pieces was not Black Hills, but Hornady! Not sure how I missed that sucker during brass prep, but I did. Anyway, I still needed a good 100 yard zero, so I dialed 1 right and two down and shot another 3 shot group. (All of these said Black Hills on head)
I am pretty pleased and feel confident that the OCW method works. If I remember correctly, the Hornady brass had 2 or 3 grains less water capacity than my Black Hills. To keep the group at .6 inches at 100 yards with two different kinds of brass tells me I have found a nice forgiving charge weight. The really nice thing is it took only 21 rounds and two trips to the range to accomplish what has taken ten times the amount of time and components in the past. I plan to use this more in the future, and just thought I would share.
-Shaky
-Shaky
