Here is the results of the velocity testing with the 200 grain Lapua and I think you will see immediately why things have been happening the way they have:
Starting with 11.0 grains of 4198:
a. 847fps
b. 943fps
Av: 895fps but this seems a little on the high side.
11.5 grains:
a. 932fps
b. 1088fps
c. 1161fps
d. 955fps
Av: 940fps (remove b &c due to velocity spike)
12.0 grains:
a. 960fps
b. 981fps
c. 996fps
d. 964fps
Av: 976fps (see that the velocities are stabilizing and there are no spikes)
So what does that tell us? Well it tells me that more powder is needed and a simple straight line graph suggests that 13.75 grains of 4198 should give 1050fps.
Fingers crossed!
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