What BC does nosler use the G1 or G7 ????

[coyotetrapper]

I noticed Berger bullets has really dropped the BC of it's bullets for long range almost 50% what does nosler use? The g1 or G7. Thanks CT

 

[Richracer1]

Berger is about the only bullet maker advertising the G7 BC numbers for their bullets, which is the reason for the low numbers - look again at their charts because they also show the G1 BC numbers as well, which are really high. All of the other makers only advertise the G1 BC numbers. I hope Nosler will start including the G7 BC numbers in their #7 manual.

 

[JD338]

Use the G1 drag for Nosler bullets.

JD338

 

[Antelope_Sniper]

The G7 is actually a much more accurate ballistics model for the modern day rifle. If I remember correctly, the base projectile is a .30 cal, 168gr spitzer boattail bullet. The G1 uses a WWI 3 inch Krups flat nose cannon shell for a base projectile. Since the G1 number is always higher, the Marketing departments encourage the use of this older, less accurate number. So in reality, Berger didn't cut their BC's, they just changes to a more accurate model.

The biggest advantage of the G7 model is that it's not velocity sensative. You will notice that Sierra often prints two BC's for it's bullets, on at a high velocity, one at a lower velocity. This would not be necessary if they switched to a G7 Model. Think of how this would affect the long range shooter (bergers core customer base). The G7 model would not degrade as the bullet velocit dropped.

 

[Desert Fox]

I'd been playing around with both! I didn't see any significant difference. I'd been using G1 base B.C in my Exbal ballistic program for a while now, and it works just fine. It doesn't even need tweaking in the field.

 

[coyotetrapper]

Desert fox when you change from g1to G7 is it changing the bullet BC or facoring in the differance? I tried JBM and it seems to my eye the BC doesn't change from G1 to G7 unless it is done internally in the program? But when I manually imput the BC rating then it makes a differance?

I'm thinking there had to be a good enough reason to change to a G7 format or why would Berger cut it's BC down???? I had a friend looking at building a 6mm/22 and wanted to use the 80 grain VLD I put in the numbers and even at a slower speed had a hard time with the drift claiming 14.6" at 600 yrds, using the G7 BC from bergers site and imputting that into JBM manually you come up with 6" of drift differance I was compairing 600-900 yrds mostly.

 

[Desert Fox]

All I did was comparing the Exbal Ballistic program using bullet BC base on the G1 Model against the JBM program using the bullet BC base on G7 Model. I used the data from the 140 grain Berger Hunting VLD from my 6.5-284 at a distance of 1000 yards. I had the accuracy of the Exbal program verified to 525 yards, since that's the farthest I can shoot at our local range. I did however have data from my 338 Lapua confirming the accuracy of the Exbal program up to a distance of almost a mile. (1600 yards to be exact) The bottom line is that, the program complemented each other as you can see the result below.

Here's the result:

Bullet Data: 140 grain Berger VLD Hunting

Velocity: 2975 fps
Sight in Dist: 110 yards
Bullet B.C G1 - .612 G7 - .313

Field Condition:

Altitude: 2000 ft.
Temperature 55.8 Degrees F
RH 49%
Pressure 27.53 in/hg


Difference at 1000 yards/ rifle zeroed at 110 yards

Exbal G1

Drop in inches at 1K: 250.6"

Elevation Adjustment: 24.0 MOA


JBM G7

Drop in inches at 1K: 249.1"

Elevation Adjustment: 23.8 MOA

As you can see the the difference is so small to warrant worrying about. IMHO, this is another one of those hype concocted by another bullet manufacturer to sell more bullet.

 

[Ridge_Runner]

but no BC numbers are set in stone, I also shoot a 140 berger in my 6.5 Gibbs, at 3340 fps In order to make POI match POA out to 1100 yards I use a G1 DF BC of .7 in my exbal program
I've had 1 bullet that the makers published BC was spot on out to 1K, that was a lapua 139 gr scenar.
RR

 

[Desert Fox]

but no BC numbers are set in stone, I also shoot a 140 berger in my 6.5 Gibbs, at 3340 fps In order to make POI match POA out to 1100 yards I use a G1 DF BC of .7 in my exbal program
I've had 1 bullet that the makers published BC was spot on out to 1K, that was a lapua 139 gr scenar.
RR

I must be one lucky guy. I don't have to tweak any of the factory published B.C of my load just to match the program.