Duh
WKR
- Joined
- Apr 5, 2023
- Messages
- 498
Hey guys can someone please help me wrap my head around this load I developed. To start, I’m shooting a Seekins havak 300WM with a banish 30 suppressor and a NF NX8.
The load is virgin Petersons long brass with 77 grains of H1000, fed 215, and a 212 eldx.
I’ve shot over two separate days at basically the same temperature and humidity and haven’t ran into pressure signs yet.
The bottom group is my first grouping for this load and ended up about 4 inches low of my previous zero, which was a significantly slower load. This was shot on 8/14/23 and the temp was 70 F.
I liked the accuracy of this new load and the numbers so I loaded up 30 more and went to zero today. As you can see, the only changes I made to the load was seating the bullet 4 thousandths longer. I did that so I would be a even 20 thou off JAM. I figured this wouldn’t cause a huge change.
I figured that I was going to be 4 inches low based on the previous group from 8/14/23 so I made a 4 MOA adjustment and hit above the cardboard target. This surprised me so I just dialed back down to my regular zero and I hit perfect vertically but a tad left. I ended up shooting a 10 shot group and made a 1/4 MOA adjustment to the right. This is the top grouping shown in the picture.
My shooting was done off a solid bipod and rear bag. I have not cleaned the barrel between these two loads. The components are all the same and the temps were pretty much the same. The only real difference between the two loads is the 4 thou longer seating depth (which I didn’t think was enough to give me that different of results). As you can see, my velocities are slightly faster in the bottom group but not by much. The Chrono was a magnetospeed v3 on a MK machine mount so I there was no barrel interference.
Why was the first group so low compared to the top group?
The load is virgin Petersons long brass with 77 grains of H1000, fed 215, and a 212 eldx.
I’ve shot over two separate days at basically the same temperature and humidity and haven’t ran into pressure signs yet.
The bottom group is my first grouping for this load and ended up about 4 inches low of my previous zero, which was a significantly slower load. This was shot on 8/14/23 and the temp was 70 F.
I liked the accuracy of this new load and the numbers so I loaded up 30 more and went to zero today. As you can see, the only changes I made to the load was seating the bullet 4 thousandths longer. I did that so I would be a even 20 thou off JAM. I figured this wouldn’t cause a huge change.
I figured that I was going to be 4 inches low based on the previous group from 8/14/23 so I made a 4 MOA adjustment and hit above the cardboard target. This surprised me so I just dialed back down to my regular zero and I hit perfect vertically but a tad left. I ended up shooting a 10 shot group and made a 1/4 MOA adjustment to the right. This is the top grouping shown in the picture.
My shooting was done off a solid bipod and rear bag. I have not cleaned the barrel between these two loads. The components are all the same and the temps were pretty much the same. The only real difference between the two loads is the 4 thou longer seating depth (which I didn’t think was enough to give me that different of results). As you can see, my velocities are slightly faster in the bottom group but not by much. The Chrono was a magnetospeed v3 on a MK machine mount so I there was no barrel interference.
Why was the first group so low compared to the top group?