Why Our BC Numbers have been Lowered (Corrected)

Posted January 30, 2009

Walt Berger established a culture that makes the success of the rifle shooters our highest priority. This core belief influences all our efforts. When we decided many years ago that we wanted to publish our G1 BCs for all of our bullets we had a bit of a problem. We do not have access to a firing range that would allow us to establish fired BCs (turns out that this was a good thing but I’ll get into that later).

Walt contacted his friend and famed Ballistician Bill Davis to ask him how we can solve this challenge. As it turns out Bill was working on software that calculates a bullet’s BC based on dimensional inputs. It was a perfect solution for us at the time. We acquired Bill’s program and went to work generating G1 BCs.

These BCs were put to the test and we received many reports that shooters were coming very close to the drops predicted using our numbers. Given the nature of various different rifles and the velocity influenced differences in G1 BCs we accepted that our numbers were as good as we could produce for the majority of rifle shooters.

A few years ago the industrious and highly intelligent Ballistician, Bryan Litz started work on a project to accurately measure the fired BC of rifle bullets from all major manufacturers. During this project Bryan shared that our published BC was consistently 3% to 5% high. After further discussion we learned that Bill Davis’ program was very accurate but the dimensions we entered into the program did not take minor realities into consideration. For example, we used the total boat tail length in our data but every boat tail has a slight radius at the base which shortens the actual boat tail length. This influences the flight of the bullet and the actual BC.

A few months ago Bryan became Berger Bullet’s full time Chief Ballistician. Since Bryan has the ability to accurately measure fired BCs with +/- 1% repeatability and since we are committed to providing shooters with the best product and data it was an obvious and simple decision to update our published BCs to Bryan’s fired numbers. These BC’s are averaged from 3000 fps to 1500 fps and corrected to ICAO standard sea level conditions. The changes are slight but do provide the rifle shooter with an enhanced ability to successfully hit exactly where they aim on the first shot. THIS is the specific reason why the BCs were changed (corrected).

I mentioned earlier that it was a good thing that we did not shoot our BCs on a local range as those available to us at the time were only good out to 200 yards. Since the G1 BC is influenced heavily by velocity any BC numbers we generated over this short range would have been inflated higher than those we achieved through Bill Davis’ program.

One of the concerns that we are hearing about our new (corrected) BC is that since it is lower shooters have the impression that they will not perform as well as they did before. The fact is that ALL of the bullets are exactly the same and have not been changed. They will fly with precisely the same trajectory as they did before we adjusted the BC to a more accurate number.

Another related concern we are hearing is now that our BC numbers are lower they are not much different than other brand’s bullets in their respective weight class. Shooters need to understand that most of the other brand’s BC’s are valid only for high velocity where BC is highest. This produces an inflated number as it would have for us if we did the same thing which is why Bergers new BC’s are average values between 3000 fps and 1500 fps. The bottom line is their numbers are not representative of the bullets average performance over long ranges where the velocity slows down. If you do not believe this there are a number of simple tests to prove this is true.

The one exception to this situation is Sierra. Sierra publishes BCs for three or more different velocities. If you take these multiple BCs and average them you will get a BC that is very accurate for most of their bullets and is comparable to the average BC given for Berger bullets. The unfortunate thing is that many shooters use only Sierra’s high velocity BC as a comparison. This is not accurate when you are comparing this high velocity BC to the averaged BC that Berger publishes.

A BC is not a marketing tool and should not be inflated (intentionally or by using inaccurate means to calculate BC) for the purposes of selling more bullets. Some will say that inflating BC is smart business but frankly, we do not agree. A BC is an important number with physical meaning that’s used to calculate the trajectory of a given bullet which enables shooters to reliably engage targets at long range. The BC should allow a shooter to hit their aim point each and every time. There are many factors that influence the location of bullet impact but an accurate BC number is an essential component in achieving the most successful shooting experience no matter which brand you shoot. The bullet makers owe it to the shooters to provide them with truly accurate information about the performance of their product and that’s what we’re committed to.

Ballistic Coefficients and the programs that use them to predict trajectories are based on the same physical laws that got us to the moon. Success in rifle shooting is arguably not quite as critical as executing a flight to the moon. However, if you think we aren’t as committed to your success as the NASA engineers were you’re wrong.

In the not too distant future there will be information readily available detailing the G1 and more appropriate G7 (for long range bullets) BCs for bullets from every commonly available brand. Once this information is readily available everyone will see that the actual level of performance of the Berger bullets in comparison to other options has not changed. You will also be able to see how much different the published BCs of other brands are compared to their actual BCs. It will be an interesting and eye opening resource.

Regards,
Eric Stecker
Executive Vice President
Berger Bullets

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