DrMike
Ballistician
- Nov 8, 2006
- 37,518
- 6,557
I managed to complete initial work-up with IMR8208XBR in my 257 Roberts. The powder did not prove to be exceptional generally. I could push 115 grain PTs to 2779 fps with 1.14 inch groups. While it is plenty good for deer, it was not better than previous work-ups with RL19 and 110 grain ABs. However, when I worked up a load using IMR8202XBR and 100 grain Hornady SPs, the results were somewhat more dramatic.
This was a modest charge of 37.5 grains of IMR8208XBR. As charge weight increased, group size increased. This produced a velocity of 2972 +/- 25 fps and a group size of 0.29 inches. It merits looking into more closely. I'll undoubtedly take this to the range again this week to look more closely. I just got a shipment of 100 grain E-Tips, and I'll be working with them soon.
This was a modest charge of 37.5 grains of IMR8208XBR. As charge weight increased, group size increased. This produced a velocity of 2972 +/- 25 fps and a group size of 0.29 inches. It merits looking into more closely. I'll undoubtedly take this to the range again this week to look more closely. I just got a shipment of 100 grain E-Tips, and I'll be working with them soon.
