#### Oliveralan

##### Well-Known Member

Hey,

I have used exbal to work out some drop data, but i cant get the computed numbers to match my real world drops. Can someone who maybe has a better knowledge of ballistics chime in and/or use a more sophisticated program and edits BC? My velocity is right around 2844fps. I am shooting a 208gr A-max. published bc is .648 or .233 G7 according to Bryan's book (this is off memory dont take my word for it).

Input parameters:

Temp: 55 degrees F

Pressure: 29.7

Altitude: 32ft over sea level

humidity: 78%

Velocity: 2844fps (measured with chrony, average over 5 shots, i know it's not much.)

Sight height: 1.64"

Zero: 100 yards

Real world drops:

100yrds -- 0 moa

200yrds -- 2 moa

250yrds -- 2.75 moa

300yrds -- 3.5 moa <-- rock solid

370yrds -- 5.75 moa

400yrds -- 6 moa <-- rock solid

these are the drops I was using most were derived from reactive targets 3.5" in diameter so allow for a little variance. 300 and 400 yard drops were on steel and I adjsted till they hit perfect center line.

I am thinking about just graphing my real world drops in excel or such and then extrapolating. Will see, i will measure drops in inches from 100 to 400 in 50yrd intervals next saturday.

I am going to texas on a boar hunt next tuesday and am trying to get this stuff ready or ill waste a day of my hunt working up drop charts, instead of just a few hours confirming it.

Thanks,

Oliver

I have used exbal to work out some drop data, but i cant get the computed numbers to match my real world drops. Can someone who maybe has a better knowledge of ballistics chime in and/or use a more sophisticated program and edits BC? My velocity is right around 2844fps. I am shooting a 208gr A-max. published bc is .648 or .233 G7 according to Bryan's book (this is off memory dont take my word for it).

Input parameters:

Temp: 55 degrees F

Pressure: 29.7

Altitude: 32ft over sea level

humidity: 78%

Velocity: 2844fps (measured with chrony, average over 5 shots, i know it's not much.)

Sight height: 1.64"

Zero: 100 yards

Real world drops:

100yrds -- 0 moa

200yrds -- 2 moa

250yrds -- 2.75 moa

300yrds -- 3.5 moa <-- rock solid

370yrds -- 5.75 moa

400yrds -- 6 moa <-- rock solid

these are the drops I was using most were derived from reactive targets 3.5" in diameter so allow for a little variance. 300 and 400 yard drops were on steel and I adjsted till they hit perfect center line.

I am thinking about just graphing my real world drops in excel or such and then extrapolating. Will see, i will measure drops in inches from 100 to 400 in 50yrd intervals next saturday.

I am going to texas on a boar hunt next tuesday and am trying to get this stuff ready or ill waste a day of my hunt working up drop charts, instead of just a few hours confirming it.

Thanks,

Oliver

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