Re: Bedding Question
Finally got around to doing an OCW. This is my first OCW. The rifle is a Mauser action with a 26" Douglas SS target barrel. It has a wood stock which is now fully glass bedded.
The OCW was shot with 168 grain Nosler HPBT and IMR 4350. The range was 300 yards with some wind from 140 degrees. There are 10 groups, with 0.3 grain increases, starting at the upper left with 68.0 grains. The shot group is always above the 1” red square. This was my first surprise. I had previously loaded some identical rounds with 68.0 grains of IMR4350 to use to get on the paper and establish where I wanted the groups to be on the target. I was using old Remington brass for these loads. The POI was zero elevation and about 2” right at 300 yards. Shot a three shot 1 1/4” group. Was pleased with this group at 300 yards. The OCW loads used brand new Nosler brass (2nds). The impact of the 68.0 grain charge with Nosler brass was three inches higher than the identical rounds with Remington brass and the groups stayed high over the course of the test. I don't think I will shoot >1,000 yards. I believe that anything >3,000 fps will get me to 1,000 yards supersonic. So a node in the 68-69 grain range may do what I want. I also want to save the 300 WM barrel. I looked at the center to center measurement of each group and also at the elevation spread within each group. I understand the change in elevation is a good indication of the robustness of the rifle and its loads with regard to locating its sweet spot. The target photos and the data follow.
This group center to center was 2.3 inches. The elevation was 0.1 MOA.
This group center to center was 2.5 inches. The elevation was 0.2 MOA.
This group center to center was 4.3 inches. The elevation was 0.4 MOA.
This group center to center was 3.8 inches. The elevation was 0.8 MOA.
This group center to center was 2.8 inches and the elevation was 0.2 MOA. The group beside it was center to center was 3.8 inches. The elevation was 0.3 MOA.
This group center to center was 3.1 inches. The elevation was 0.6 MOA.
This group center to center was 2.4 inches. The elevation was 0.5 MOA.
This group center to center was 2.3 inches. The elevation was 0.4 MOA.
This group center to center was 3.5 inches. The elevation was 0.6 MOA.
This is the data.
Looks like I need to start refining the load around 68.3 grains. Looks like the old girl is carrying them pretty good.
Would appreciate any comments.