Re: 308 Win, 208 AMax, RL17
Finally i'm able to report back with some data, I went to the range on Tuesday but it was raining, no chrono data, and the rifle broke. Fixed the rifle, went back out yesterday to repeat the testing, didn't take the skyscreens with me like a 'tard, no chrono data, however started to see a trend with COL settings. Was bummed out about the chrono problem and the wife made a fantastic suggestion, she said, go load up some more rounds and go out tomorrow morning first thing. So I did, and today I didn't forget my skyscreens, and I didn't go to the public range, I went to where I can shoot from the prone, and take my time, and not get rushed.
It's been quite a long while since i've shot from the prone, and I was trying to make sure my technique was correct, but I don't think it was very consistent. Oh well, the groups weren't terrible, I had some oddities due to me shifting holds in the middle of a group, pulling rounds, or not shooting on my NPA. But the chrono data all came through, no glitches, no hiccups, just 100% satisfactory data.
My loads were all 49.0gr RL17 behind the 208Amax with CCI200 primers and Lapua brass trimmed to 2.005", and neck sized 3/4 of the neck. I haven't done just neck sizing in a while, I'm going to do a side by side comparison of identical loads where the only variation is Full Length sized, and neck sized, and see if there is any improvement between the two. The only variation's in these loads was the COL. I've suspected that my second load with a COL of 3.260" (with my adapter) was in a sweet spot and today I confirmed it.
Load 1 3.250"
Lo 2497
Hi 2540
Avg 2515
ES 42.99
SD 15.9
Load 2 3.260" (Good load)
Lo 2530
Hi 2540
Avg 2534
ES 10.62
SD 3.87
Load 3 3.265"
Lo 2518
Hi 2545
Avg 2534
ES 27.01
SD 11.18
Load 4 3.270" (touching lands)
Lo 2532
Hi 2552
Avg 2542
ES 19.22
SD 7.87
Load 5 3.275 (slight jam)
Lo 2561
Hi 2587
Avg 2573
ES 26.29
SD 11.74
I find it kinda funny that the longer the OAL I went, the velocity climbed. I'm happy with the chrono results today, however my groups weren't making me as happy, but I think I know how to fix that, just need more practice shooting from the prone.
BTW, one question, can I be very sure that a flyer was cause by something I did (or didn't do) while firing that round is nothing shows on the chrono to suggest that there was a problem with that round?
Branden