Re: I am SOOOOOO confused. HEEEEEEEELP!!!!!!!!!!!!!!!!!!!!!!
Well Craig here's a quote from a site that has what the G functions are for [ QUOTE ]
G1.1 - Standard model, Flat Based with 2 caliber (blunt) nose ogive
[/ QUOTE ].
As you can see this simply will not work as it doesnít describe the bullet in question.
The G5 was [ QUOTE ]
G5.1 - For Moderate (low base) Boat Tails - 7į 30' Tail Taper with 6.19 caliber tangent nose ogive
[/ QUOTE ] [ QUOTE ]
G6 is G6.1 - For flat based "Spire Point" type bullets - 6.09 caliber secant nose ogive
[/ QUOTE ] and finally G7 [ QUOTE ]
G7.1 - For "VLD" type Boat Tails - long 7į 30' Tail Taper with 10 caliber tangent nose ogive
[/ QUOTE ].
Now compared to a Berger 185 grain bullet and the A-MAX 178 grain bullet the differences are the boat tail is shorter, and not at the same angle, the shank length is very close to the same but the ogive is shorter but very close to the same radius.
Since the G5 function didnít match his drop data I switched to the G7, the G5 is more of what the A-Max looks like but the data didnít correspond to the real world trajectory he stated.
I placed a call to Hornady and they suggested using the G1 function, when I explained to the gentlemen that the G1 function had already been used and was not matching up with real world data and that JBM software matched very closely he said thatís interesting and I will pass that on to our ballisticians.
For whatever thatís worth if the numbers match and match at more than one interval then obviously using the G7 function with his data is correct. When I say correct itís not correct in the meaning of ruling out any other possibilities just that with his data, the JBM program and the G7 function used it was correct for his data. Keep in mind though that two points in the trjectory path are known, the 300 yard zero and the 37.7 inches of drop, the G7 function placed the bullet at exactly where he said his dropped to or very close so much so that it isnt worth aruging about.
Mike the BC never changes between G functions what changes is the drag and how effective the bullet is at beating it.
I used the same BC that Hornady claims from their web site.
One key element here is we still do not know the altitude which may or may not provide an answer as to why the G7 function worked while none of the others didnít.
According to this site if you have a program that allows multiple inputs at different ranges it will calculate for you the BC at those ranges for the A-Max bullet the Bc2 through BC4 limits are all 1.00.
Jb100br may be on to something also, however it is highly coincidental that 37.7 matched perfectly for the G7 function, the odds of the wind blowing the bullet upwards and matching exactly 37.7 is by chance I think but will not rule it out as a possible factor in the trajectory.