Pretty simple question. Should I be using the G1 drag model with my 208g Amax? Im shooting a 300 winmag, Reloader 22: 71g, 2870FPS.
Range Report Drag Model Help
- Thread starter Jig Stick
- Start date
Re: Drag Model Help
I prefer G7 model (0.324 for the 208 gr.) as opposed to the the G1 model (0.633) for ballistic programs.
I prefer G7 model (0.324 for the 208 gr.) as opposed to the the G1 model (0.633) for ballistic programs.
Re: Drag Model Help
im using the JBM Ballistic program on my Ipad / Iphone. What variables are different between the two drag models? I ordered Applied Ballistics for Long Range Shooting, and im sure the info that im looking for is in there, but it hasnt been delivered yet. And im going coyote hunting today. I like using my phone to cross reference my DOPE sheet.
im using the JBM Ballistic program on my Ipad / Iphone. What variables are different between the two drag models? I ordered Applied Ballistics for Long Range Shooting, and im sure the info that im looking for is in there, but it hasnt been delivered yet. And im going coyote hunting today. I like using my phone to cross reference my DOPE sheet.
Re: Drag Model Help
<div class="ubbcode-block"><div class="ubbcode-header">Originally Posted By: Jig Stick</div><div class="ubbcode-body">im using the JBM Ballistic program on my Ipad / Iphone. What variables are different between the two drag models? I ordered Applied Ballistics for Long Range Shooting, and im sure the info that im looking for is in there, but it hasnt been delivered yet. And im going coyote hunting today. I like using my phone to cross reference my DOPE sheet.</div></div>
Jeepers Jig Stick, I don't know what kind of math goes into figuring the G7 but it probably is a few pages long. Using the G7 will just get you closer to what you will encounter in real life for a high speed bullet. G1 is based on a flat based spitzer and the comparison between it and boat tail bullets will give you a much higher BC.
The G7 is closer to the newer bullet shapes and this will give you a lower BC. The G1 is preferred by a lot of bullet manufacturers because of the higher numbers and that SELLS bullets. But for the long range shooter, G7 will be closer in calculated trajectory to your actual bullet drop so it is the one you would want for long rang shooting when calculating at longer distances.
I copy and pasted this little chart from Wikipedia.
http://en.wikipedia.org/wiki/Ballistic_coefficient
G1 or Ingalls (by far the most popular)
G2 (Aberdeen J projectile)
G5 (short 7.5° boat-tail, 6.19 calibers long tangent ogive)
G6 (flatbase, 6 calibers long secant ogive)
G7 (long 7.5° boat-tail, 10 calibers tangent ogive, preferred by some manufacturers for very-low-drag bullets[10])
G8 (flatbase, 10 calibers long secant ogive)
GL (blunt lead nose)
<div class="ubbcode-block"><div class="ubbcode-header">Originally Posted By: Jig Stick</div><div class="ubbcode-body">im using the JBM Ballistic program on my Ipad / Iphone. What variables are different between the two drag models? I ordered Applied Ballistics for Long Range Shooting, and im sure the info that im looking for is in there, but it hasnt been delivered yet. And im going coyote hunting today. I like using my phone to cross reference my DOPE sheet.</div></div>
Jeepers Jig Stick, I don't know what kind of math goes into figuring the G7 but it probably is a few pages long. Using the G7 will just get you closer to what you will encounter in real life for a high speed bullet. G1 is based on a flat based spitzer and the comparison between it and boat tail bullets will give you a much higher BC.
The G7 is closer to the newer bullet shapes and this will give you a lower BC. The G1 is preferred by a lot of bullet manufacturers because of the higher numbers and that SELLS bullets. But for the long range shooter, G7 will be closer in calculated trajectory to your actual bullet drop so it is the one you would want for long rang shooting when calculating at longer distances.
I copy and pasted this little chart from Wikipedia.
http://en.wikipedia.org/wiki/Ballistic_coefficient
G1 or Ingalls (by far the most popular)
G2 (Aberdeen J projectile)
G5 (short 7.5° boat-tail, 6.19 calibers long tangent ogive)
G6 (flatbase, 6 calibers long secant ogive)
G7 (long 7.5° boat-tail, 10 calibers tangent ogive, preferred by some manufacturers for very-low-drag bullets[10])
G8 (flatbase, 10 calibers long secant ogive)
GL (blunt lead nose)
Re: Drag Model Help
Short answer is that G1 varies more with velocity (the higher the velocity the higher the BC) G7 more accurately reflects the the trajectory of bullets we typically use for long range shooting. What bullet you are using dictates what drag model you want to use.
Short answer is that G1 varies more with velocity (the higher the velocity the higher the BC) G7 more accurately reflects the the trajectory of bullets we typically use for long range shooting. What bullet you are using dictates what drag model you want to use.
Re: Drag Model Help
Here's a thread with a few guys that know more about this subject than most anyone:
http://www.snipershide.com/forum/ubbthreads.php?ubb=showflat&Main=213252&Number=2398996
Hope this one helps.
Here's a thread with a few guys that know more about this subject than most anyone:
http://www.snipershide.com/forum/ubbthreads.php?ubb=showflat&Main=213252&Number=2398996
Hope this one helps.
Re: Drag Model Help
G7 is more accurate than G1 for bullets shapped like the G7 standard bullet (like most of the BTHP we shoot).
Inside 600-700 yards it maters little.
G7 is more accurate than G1 for bullets shapped like the G7 standard bullet (like most of the BTHP we shoot).
Inside 600-700 yards it maters little.
Re: Drag Model Help
Gotcha. I didnt know the rationale for choosing one over the other, thats all. But now I do. Thanks guys.
Gotcha. I didnt know the rationale for choosing one over the other, thats all. But now I do. Thanks guys.
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