huntnidaho
Active Member
- Joined
- Jun 30, 2017
- Messages
- 30
So I have a couple more range trips behind me using this powder in my Christensen Ridgeline 7mm RM. I am shooting the Berger 175 Elite Hunter in this rifle. I am using load data from Hodgdon for the 180 Berger. Starting load is 67.7grains, Max is 72.8grains according to their data.
I did a charge ladder yesterday from 68 to 72.5 grains. I hit heavy bolt lift at 72.5 grains. Went back today with some groups loaded at 70, 70.5 and 71 grains. All shot well, but 70 grains was in the .3's at ~2930fps. Groups at 70.5 and 71 were still approaching .5". ES/SD was also best at 70 grains, both single-digit, granted sample size is small. I think I will stick around 70 grains, zero the rifle and stretch it out. I'll also keep logging chrono data. I am cautiously optimistic so far. It will be interesting to see how it reacts to temp swings and how the ES/SD hold up.
As a side note, I've used both Retumbo and RL33 in this gun with this bullet. IMR 8133 seems to take about 1.5 grains more than Retumbo to hit the same velocity and 4 grains less than RL33 according to my notes. I struggled to find good, consistent ES/SD with Retumbo. RL33 was actually working well, at 74 grains I had a load pushing the same bullet around 2950fps at .5-.6 MOA or so at 100 yards and good spreads. As far as the CFE claims of 8133, I haven't yet cleaned my barrel so I cannot comment on that.
So far, so good.
I did a charge ladder yesterday from 68 to 72.5 grains. I hit heavy bolt lift at 72.5 grains. Went back today with some groups loaded at 70, 70.5 and 71 grains. All shot well, but 70 grains was in the .3's at ~2930fps. Groups at 70.5 and 71 were still approaching .5". ES/SD was also best at 70 grains, both single-digit, granted sample size is small. I think I will stick around 70 grains, zero the rifle and stretch it out. I'll also keep logging chrono data. I am cautiously optimistic so far. It will be interesting to see how it reacts to temp swings and how the ES/SD hold up.
As a side note, I've used both Retumbo and RL33 in this gun with this bullet. IMR 8133 seems to take about 1.5 grains more than Retumbo to hit the same velocity and 4 grains less than RL33 according to my notes. I struggled to find good, consistent ES/SD with Retumbo. RL33 was actually working well, at 74 grains I had a load pushing the same bullet around 2950fps at .5-.6 MOA or so at 100 yards and good spreads. As far as the CFE claims of 8133, I haven't yet cleaned my barrel so I cannot comment on that.
So far, so good.
