Kinda long, but please bear with me.
I've been using FFS for years, & have always been able to get verry accurate solutions with published BC's, & my chrony. Until now.
Since switching to Hornady's new 225gr HPBT, I have not been able to get anything close with any of the published BC's, & my chrony'd velocities.
There are several ways I can MAKE IT give me accurate solutions.
Baseline:
300WM with Hor 225 HPBT Moly'd
Published BC-.670
MV with my chrony-2820 fps.
29.78" hg, 67* F, 62% RH. @ 300' ASL (I use station pressure measured with my Kestrel)
Zeroed @ 100 yd. I went to a high altitude for some hunting, & did some ELR with this solution.
24.77" hg, 58* F, 45% RH, 5400' ASL Beautiful day. Ranged a rock @ 1304 yd, plugged the data in, & it gave me a solution for 38,8 moa. My round hit several feet high.
I went to the .690 BC I've seen here. Solution said 38.2 & was still feet high. I was making hits @ 35.7 moa.
The next day after I adjusted the BC to .711, & MV to 2860 I fired on a rock @ 1490. MY solution was right on target.
After I went, to JBM, & did some fiddling around with the G7 BC of .351, I was able to adjust my MV up to only 2840 fps & got the right solution for the conditions.(My chrony could be that far off I guess)
Now I can get the actual solution out of FFS several ways.
1- I can use what I made work, & call it good.
2- Use my measured MV of 2820, & a G1 of .750
3- Use the .690 BC, & MV of 2883 fps.
4- Use BC of .730, & MV of 2840 fps.
I've never had to do anything other than make a DK adjustment on any of the several other loads I've used in the past to get correct solutions, so which should I use?
Thanks for bearing with me. Looking forward to your replies.
I've been using FFS for years, & have always been able to get verry accurate solutions with published BC's, & my chrony. Until now.
Since switching to Hornady's new 225gr HPBT, I have not been able to get anything close with any of the published BC's, & my chrony'd velocities.
There are several ways I can MAKE IT give me accurate solutions.
Baseline:
300WM with Hor 225 HPBT Moly'd
Published BC-.670
MV with my chrony-2820 fps.
29.78" hg, 67* F, 62% RH. @ 300' ASL (I use station pressure measured with my Kestrel)
Zeroed @ 100 yd. I went to a high altitude for some hunting, & did some ELR with this solution.
24.77" hg, 58* F, 45% RH, 5400' ASL Beautiful day. Ranged a rock @ 1304 yd, plugged the data in, & it gave me a solution for 38,8 moa. My round hit several feet high.
I went to the .690 BC I've seen here. Solution said 38.2 & was still feet high. I was making hits @ 35.7 moa.
The next day after I adjusted the BC to .711, & MV to 2860 I fired on a rock @ 1490. MY solution was right on target.
After I went, to JBM, & did some fiddling around with the G7 BC of .351, I was able to adjust my MV up to only 2840 fps & got the right solution for the conditions.(My chrony could be that far off I guess)
Now I can get the actual solution out of FFS several ways.
1- I can use what I made work, & call it good.
2- Use my measured MV of 2820, & a G1 of .750
3- Use the .690 BC, & MV of 2883 fps.
4- Use BC of .730, & MV of 2840 fps.
I've never had to do anything other than make a DK adjustment on any of the several other loads I've used in the past to get correct solutions, so which should I use?
Thanks for bearing with me. Looking forward to your replies.