Berger Bullets' Move To The G7 Standard BC: Berger Bullets' Move To The G7 Standard BC By Bryan Litz, Chief Ballistician For Berger Bullets A Better Ballistic Coefficient All_Bullets The G7 BC’s are average values from 3000 fps to 1500 fps, and there’s very little variance. This represented a dramatic improvement in the accuracy of performance data at that time. The bullet info … The next item listed is the bullets G7 BC. G6 – G6 are flatbase bullets with a 6 cailber secant ogive. If one were to use the average of the Sierra BC’s (.437) instead of .450 for the ‘advertised’ Sierra BC, the Table 2 comparison would still have error, but it wouldn’t be as bad. G7 bc values remain constant regardless of the starting muzzle velocity. Here's the BC information I collected from Sierra's website for two of the .308 bullets. Do you suppose this just means the library does not have a G7 for the Nosler? Sierra GameKing Bullets are designed for hunting at long range, where their extra margin of performance can make the critical difference. I have got pretty good results from JMB using G1 at .490 rather than .505 since the average of G1 BC for the 175 Sierra is around that for the 175. When comparing BCs of different bullets, it is important to use an apples-to-apples approach. During testing with an Oehler 88 at 1000 yards these bullets provided a measured G1 BC of .620! ! When compared to a G7 BC, the G1 is typically higher. Sierra has released load data for these four new projectiles: 22 caliber 95gr HPBT MatchKing #1396, Sierra MatchKing bullets have very thin jackets and are held to exacting tolerances in diameter and weight. Does anyone know of a source to get G7 BC's for Sierra bullets, they only list G1's on their website? So in reality, Berger didn't cut their BC's, they just changes to a more accurate model. The Spitzer is a very popular and aerodynamic bullet shape. New to Midsouth Shooters and to Sierra, the Gamechanger Tipped GameKing bullets are the perfect blend of exceptional Ballistic Coefficients (BC), Accuracy, and Deadly Terminal Performance on tough wild game. 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. Military Caliber G7 BC Table. The biggest advantage of the G7 model is that it's not velocity sensative. It allows you to customize the shooting conditions to mimic the ballistics performance of your favorite load in various conditions and environments. Meplat = < 0.020. They always needed sorting to get the best results, but were accurate and had a slight BC gain over the 105’s. (inches) .264 Weight (grains) 142 Sectional Density .291 Ballistic Coefficients and Velocity Ranges .626 @ 2850 fps and above .611 between 2400 and 2850 fps .606 between 2050 and 2400 fps .581 @ 2050 and below Important: Since there are thousands of bullet shapes the Ballistic Coefficient calculations made below are not 100% accurate, if you are shooting out past 400-500+ yards your going to need to get the exact BC from the bullet's manufacturer. PS I loved the 257 class rifles and used a … What have we learned: 1. To appreciate what BC can do for performance, let’s compare an old 150-grain round-nose .308 bullet from the early 20th century to Winchesters 150-grain Ballistic Silvertip of today. G7 is not better then G1 but it is only better with bullets with boat tails that are better for long range shooting. These Hollow Point Boat Tail bullets have a small meplat to produce a higher ballistic coefficient. I do realize that Sierra lists only the G1 BC's on their website (as does Federal on their shamefully awful website), but the design of the SMK is a much more similar profile to the G7 bullet, and should be more accurately represented by using the the G7 drag model calculations. And here's the Sierra website link to the source of this information: Ballistic Coefficients - Sierra Bullets - The Bulletsmiths Simply select the caliber bullet you're interested in researching into … We are working on a massive list, but this list won't be ready for a few weeks or months. Voilá! This data is only usable if you have software capable of handling the G7 and G8 drag models.