I just started testing a new to me combination...a 10 twist 6 Grendel. I fired about 20 rounds yesterday using 6 ARC bolt gun data with AA2460. Five shot groups were about .200 or so...not bad at all.
I just loaded up the same 90gr Berger wit 29.7gr of 8208 at .024 in, from just touching the lands. Only one five shot group, so probably luck but the first shot was most of the vertical, as it was the highest in the group. Didn't even touch the tuner and other than an educated guess, no idea of velocity yet. I'll try to chrono it tomorrow, though. Just set the powder measure to DUMP 29.7gr and loaded 5 rounds at the same depth I found best in my very limited test yesterday with AA2460.
The rifle is my UBR Unlimited Borden BRM Drop Port. with a new Krieger 1-10 twist 1.250 straight that I cut at about 25"long for gun handling reasons only.
I cleaned it well overnight and there was virtually zero copper or fouling, even on the first 20 rounds. I normally do a one shot and clean break in process but this one never fouled at all to speak of.
Anyway, I hope it holds up is all I can say. Pic of first group coming! Again, clean, cold bore and the first shot was most of te vertical.
Sorry...hard to hold the calipers still with one hand and take a picture with the other. It was too easy to shoot! I think I might have something here!
I should add that this load is pretty warm. It shows no problems in MY rifle but the obligatory rules of start low and work up at your own risk apply.
I just loaded up the same 90gr Berger wit 29.7gr of 8208 at .024 in, from just touching the lands. Only one five shot group, so probably luck but the first shot was most of the vertical, as it was the highest in the group. Didn't even touch the tuner and other than an educated guess, no idea of velocity yet. I'll try to chrono it tomorrow, though. Just set the powder measure to DUMP 29.7gr and loaded 5 rounds at the same depth I found best in my very limited test yesterday with AA2460.
The rifle is my UBR Unlimited Borden BRM Drop Port. with a new Krieger 1-10 twist 1.250 straight that I cut at about 25"long for gun handling reasons only.
I cleaned it well overnight and there was virtually zero copper or fouling, even on the first 20 rounds. I normally do a one shot and clean break in process but this one never fouled at all to speak of.
Anyway, I hope it holds up is all I can say. Pic of first group coming! Again, clean, cold bore and the first shot was most of te vertical.
Sorry...hard to hold the calipers still with one hand and take a picture with the other. It was too easy to shoot! I think I might have something here!
I should add that this load is pretty warm. It shows no problems in MY rifle but the obligatory rules of start low and work up at your own risk apply.
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