300wm tuning help

[Zero333]

What should I do? I loaded 10 .300 win. mags. with CCI BR2 primers by accident I was using Winchester Large Rifle Magnum primers. Do I need to pull the bullets or could I shot them?
Hornady brass
IMR 4831 74 grains
Nosler Accubond 180 gr.

You will be fine... In one of my 300win's I use 210m with H-4831. I chronographed that load with 215 and 210 back to back and there was no difference in velocity or group size or point of impact.

I do however stay away from BR2's in freezing temps cause I've had 2 duds with them. This was in very cold temps with 308win.

 

[Vandy321]

I didnt test the 250 at 100. I always test my 100 yard loads at 500 anymore because this is not the first time this has happened. Not always has it happened. I switched back to the 215 just to verify and sure enough right back to the same vertical. I wished I still had the targets but it's obvious when you put them side by side the 250 was better.
Didnt think I needed to shoot the 250 at 100 sure looked like I had "the load" with the 215
Untill I stretched it out to 500.

Thanks to Sherm for the primer suggestion. Will take this load out and stretch it out, but seems to have solved my ES problem.

Sorted bullets, no real change in my 215m ES, but will continue to do it, too easy not too.

Did run 30 rounds over a chrono with 3 dif primers. 10 of each. Pretty crazy results.

Fed GM215s: ES 25, SD 9.8, Ave 2981
Win LRM: ES 41, SD 16.8, Ave 2996
CCI 250: ES 8, SD 3.6, Ave 2988

CCIs grouped at .66

Im not sure I can shoot this 300wm much better than .5, so im pretty happy. I think groups will tighten up a little more as I get better behind the rifle.