85 grain ballistic tips

[DIBBS]

For those of you shooting Nosler .257 85 grain ballistic tips, what are you using for a ballistic coefficient? I have been using
.168 G7 and .329 G1

I am re-checking all of my inputs for the ballistic program, because past 600 yards my shots are hitting low. I plan to try and get out to the range tomorrow to do some more testing.

TIA

 

[Lone Hunter]

Formula I was taught is ( G1bc x .512 = G7bc ). According to this your G7 bc of .168 should be close. It is better to true it up with actual shooting than trusting the numbers I have found. For the distance I have been shooting the G1 has been very close.

Edit to add: They suggest G7 for boat tail bullets and G1 for Flatbase.

 

[DIBBS]

I'll go back and re-measure everything, and chronograph my loads a second time. Still using the same lot of powder, and appears that the BC is what it should be. Not sure why the dope would be spot on to 600 yds, and then way low past that but I will experiment and adjust the BC a bit if it doesn't match up.