I figured I would give an update on what i’ve done in terms of working up a load for my 6.5 PRC that I had built last winter. I’m shooting ADG brass, CCI 200 Primers, and Berger Hybrid Target 140’s. I’ve made a few changes to the powder as the barrel has broken in.
We started with Retumbo, as it was all I had at the time. I really wanted to use a Hodgdon Extreme powder because of their reputation of being very temperature stable. I wasn’t able to find H4831sc or H1000 at that time. We found a load that was shooting really dang good at 58.6 grains of Retumbo within about 50 rounds. By 150 firings this combination was no longer working well. I was getting extreme spreads of almost 100 fps. I’m not entirely sure on why that was, but I attribute it to the barrel speeding up and Retumbo being too slow of a powder.
I decided to try H4831sc. I settled on a load that was shooting awesome at 2940fps. 54.8 grains. I shot a local practice prs match which was 100 rounds and it shot awesome all day. I took it out to Montana on a elk scouting trip and shot 50 rounds at prairie dogs. Even shot one at 650 yards on the second shot which I thought was pretty good! It shot awesome until the last 4 rounds all of a sudden I got heavy bolt lift. I put it away and brought it home and cleaned it really well with wipe out patch out. I was at 350 rounds and it hadn’t been cleaned since 125 rounds.
I shot again with the same loads and had slight heavy bolt lift on some of the rounds and if you look you can find a faint ejector mark on some of the cases. My average velocity was 2970. ES of 25, but SD of 9 over the course of 25 shots. I figured that was acceptable for a sample size that large, and it was shooting very accurate. My first three shots on freshly painted steel at 600 yards were 3″.
Last weekend I decided to drop my charge down a full grain and do a OCW test at 100 yards. I think i’m going to anchor in at 53.5 grains of H4831sc. I’m still on the fence of going with H1000. The pressure ladder I did was very promising as far as how stabile the speed was and more importantly, how accurate each shot was.
I just thought I would give an update here in case anyone else was loading for 6.5 PRC. I’m really new to this and have learned a ton about the load development process. It’s crazy how much the barrel’s speed up and settle in. The original pressure ladder I did for H4831sc didn’t show pressure until a full grain of powder more than what it currently does. Which is 54.8
I’m pretty proud of the shooting from this last test. For group size comparison, the group on the 53.2 grain charge with the low flier (which was the only shot I pulled) measures right at .5 inches. I learned a lot of shooting techniques from Primal Rights article section. The rifles barreled action was built by TS Customs out of Miller SD.
Attachments:
H1000-velocities.jpeg
labradar.jpg
target.jpeg
H4831sc-velocities.jpeg
Gotta start somewhere! I definitely don’t have the ideal gun for these style of matches, but i’m so new to it that any exposure and practice is good.
