I also tried running the numbers with a BC of 1.25 and thats still to low. I also tried running the numbers shooting at an angle. They came out closer with a 30-35 degree shooting angle, but only work from 300-600 or from 600-800 and there still not right on. Something's got to be wrong????
Just ran the numbers again with a MV of 3350 and the numbers come out much closer. Also tried the match the trajectory using your come ups, and exbal calculates an MV of 3401 with using a BC of .512 but the 800 yd comes up shy at 13.5
I'm just learning all the tools of this Exbal software, (got it last week). I'd have to say thats its a pretty good program.
Probly didn't help, but I tried [img]images/icons/smile.gif[/img] Good shootin
It would be helpful if you could tell us what your scope height above the bore is... using JBM on the web, it appears to make a significant difference. Me thinks your chrono may be b0rked? That's the only way I could come close to your numbers:
Jeff, I would have to say that my velocity is pretty much right on. Reason is simply this is not a new wildcat and there have been lots of shooters who have achieved this type of velocity. They have never achieved 3100 to 3200fps with a 24" barrel without blowing themselves to kingdom come.
Pretty much impossible too with so little powder. In line with performance from its closest cousin, the 270 Win.
Also, I have used this Chrony with other rifles and they have all "agreed".
Now if the chrony cannot be trusted at 10ft. Why would I trust its readout at 100yds?
So the only error possible is that the chrony is reading too fast. If that were the case, the BC would be even HIGHER. Now, that would be seriously screwy.
I have attached a pic in another post (my new 6.5 toy) so that you can see that this is a very standard rifle and scope set up. Scope height is pretty much 1.5", etc.
My suggestion is still that any 6.5 shooter get some of these SST's and shoot them. At 2975fps, do you get the same or similar drop?
The correct BC may or may not be the 0.9 or 1 but it certainly is above 0.6. Either way, this is a bullet worth further investigation.
Sorry I'm not questioning your results only trying to understand them better. This stuff ain't rocket science, but there are the laws of physics and is usually pretty straight forward.
I've never had much luck with my two chrony's. But getting an average velocity readings at exactly 100 yards and having your average muzzle velocity will establish your correct BC and then we can use the different drag models to better fit it to your results.
Just trying to help. There are a lot of explanations for your results, but having exact numbers help.
[ 08-18-2004: Message edited by: Jeff In TX ]
Distance is not an issue, but the wind will make it interesting!