Finding additional coefficients?

[Stormdrane]

I've managed to true out my BC to dead nuts accurate up to around 900m, at which point POI starts to falter to >1mil from calculations. I'm still new to a lot of the physics and sop involved here, but this seems consistent with how I would expect the coefficient to falter with velocity. My question here is would you now begin truing a new BC to have on file for that specific range and ambient temperature, and start accumulating these in your dope sheet? It feels like there is a much better procedure for this, but I dont have anything that can run custom drag modeling. Thanks in advance.

Cheers

 

[Deleted member 10043]

What are you using to start off with.

 

[Stormdrane]

.308 Remington 700 running M118LR
Glass is a Leupold Mk 4,

Going through Horus' AtragMX in G1

 

[Deleted member 10043]

900 meters is about the effective limit for that ammo. But converted G7 would be more appropriate don't you think? Obviously your computer is limited to G1. JBM online is worth a try.

 

[Stormdrane]

I agree whole heartedly, and Ive gotten slightly better results by running the G7 off my foretrex (although a bit more cumbersome to enter data). Obviously Im not putting any kind of a good grouping at that distance, but its consistant enough to show the trend of what the calculations seem to be doing. I'm hoping to ease into .338 in the near future, but Im not sure if that would prolong the degradation of the model or I would need to adapt to it further in order to push the distance. Thank you so much for the help