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Berger Releases NEW Bullet BCs
nononsense
Member Posts: 10,928 ✭✭✭✭
What's going on?
In a short time, you will notice changes to the advertised BC's for Berger bullets on the box labels and website.
How was BC established in the past and why change?
Historically, Berger BC's have been calculated using a computer program written by Bill Davis specifically to predict BC's. The program takes the bullet's design dimensions as inputs, and returns a predicted BC that's acceptably accurate for a computer prediction (+/- 10%). Although the old way was `acceptable', there is a more accurate way to determine BC; by actually test firing the bullets, which is how our BC's will be established from now on. The experimental procedure and equipment that is being used to measure BC has been under development for over a year, and is able to produce results that are repeatable within +/- 1%.
How much will the BC's change?
On average, the new BC's are a little lower than the old ones, about 4 to 5% on average. To put this in perspective, a 4 to 5% difference in BC equates to about 8 inches (out of ~300) difference in drop at 1000 yards for a typical long range round, and about 4 inches (out of ~70) difference in wind deflection in a 10 mph crosswind at the same distance. Some BC's will change more than 4 to 5%, some will change less. Bottom line is that we believe the new BC's are more accurate because they're based on repeatable testing and measurement as opposed to computer predictions that are based on theory.
Should I care?
Target shooters shooting at 'known distance' typically don't care about BC for accurate trajectory prediction. Just so you can get on target, you can walk the rounds in with sighters. Target shooters care about accurate BC's more for comparison purposes, specifically wind deflection comparisons.
Long range hunters, tactical shooters, and any other application that involves shots at various unknown distances rely on trajectory tables generated using the bullet's BC. The more accurate the BC is, the more likely the drop chart will result in hits for the shooter.
It's important to realize that the bullets themselves are exactly the same as they've always been. The designs haven't changed at all. We're simply using a more accurate way to establish the BC's for the same bullets.
More details on the 'new' BCs
The new advertised BC's for Berger bullets will be referenced to the G1 standard (same standard used for all other brands) and will represent the average BC from 3000 fps to 1500 fps, which covers the `typical' velocity range that our bullets operate at. Of course, some bullets will operate slightly above or below that band, and minor inaccuracies can be incurred because of that. I chose to use one average value for BC rather than defining it in velocity bands (like Sierra does) for a couple reasons. First of all, many shooters misunderstand the velocity bands, and simply apply the high velocity BC for the entire trajectory (perhaps thinking the BC is related to just the muzzle velocity). This will obviously cause inaccuracy in a trajectory prediction, and misrepresent the bullet when comparing it to others. Also, not all ballistic software programs have the ability to define multiple BC's.
Some Info on other brands BC's
Just for some context, not all bullet makers establish BC in the same way. Sierra test fires their bullets for BC, and reports different BC's for each velocity band. I've tested many Sierra bullets for BC, and with few exceptions, my tests have been in very good agreement with their claims (usually within +/- 3 to 5%). In order to make a fair comparison between Berger and Sierra bullet BC's, you have to average all of the Sierra BC's for each velocity band, and compare that to the single Berger BC. If you only compare the high velocity BC given by Sierra to the average Berger BC, it's not a true `apples-to-apples' comparison. I believe that both Hornady and Nosler also test fire their bullets for BC, however, their advertised values only apply for high velocity (tests are conducted only to 100 or 200 yards I think). This makes it hard to compare them to the Berger number. I'm not sure how Lapua calculates their BC's.
The effect of this change on 'Marketing'
We understand that slightly decreasing our advertised BC's may affect how `attractive' Berger bullets are to some customers who are impressed with high BC's alone. However, the amount that our advertised BC's are decreasing is so small that there are few cases where we change positions on the totem pole. In other words, if we had the highest BC before the change, we still probably have the highest BC, but maybe by a smaller margin. There's also the accuracy of the other brands advertised BC's to consider when looking at the totem pole.
To be honest, I've always hated the idea of BC being used as a marketing tool (although I can't deny that it can be effectively used as such). The BC of a bullet is an important number that people use to analyze the performance of rifles, calculate trajectories, and hit targets. I believe that our new BC's are more accurate, and will help shooters achieve better success which is what I think it's all about.
Future Plans
There are plans to improve the way we represent our BC's in the future that's less tied to velocity which will clear up a lot of the ambiguity on the subject. It will be a challenging transition, and we'll make it when we feel all the pieces are in place to give it the best chance of success. Until then, we feel that these experimentally determined, average G1 BC's are the best way to go.
I am happy to address any questions or concerns related to this change.
-Bryan
Ballistician
Berger Bullet
In a short time, you will notice changes to the advertised BC's for Berger bullets on the box labels and website.
How was BC established in the past and why change?
Historically, Berger BC's have been calculated using a computer program written by Bill Davis specifically to predict BC's. The program takes the bullet's design dimensions as inputs, and returns a predicted BC that's acceptably accurate for a computer prediction (+/- 10%). Although the old way was `acceptable', there is a more accurate way to determine BC; by actually test firing the bullets, which is how our BC's will be established from now on. The experimental procedure and equipment that is being used to measure BC has been under development for over a year, and is able to produce results that are repeatable within +/- 1%.
How much will the BC's change?
On average, the new BC's are a little lower than the old ones, about 4 to 5% on average. To put this in perspective, a 4 to 5% difference in BC equates to about 8 inches (out of ~300) difference in drop at 1000 yards for a typical long range round, and about 4 inches (out of ~70) difference in wind deflection in a 10 mph crosswind at the same distance. Some BC's will change more than 4 to 5%, some will change less. Bottom line is that we believe the new BC's are more accurate because they're based on repeatable testing and measurement as opposed to computer predictions that are based on theory.
Should I care?
Target shooters shooting at 'known distance' typically don't care about BC for accurate trajectory prediction. Just so you can get on target, you can walk the rounds in with sighters. Target shooters care about accurate BC's more for comparison purposes, specifically wind deflection comparisons.
Long range hunters, tactical shooters, and any other application that involves shots at various unknown distances rely on trajectory tables generated using the bullet's BC. The more accurate the BC is, the more likely the drop chart will result in hits for the shooter.
It's important to realize that the bullets themselves are exactly the same as they've always been. The designs haven't changed at all. We're simply using a more accurate way to establish the BC's for the same bullets.
More details on the 'new' BCs
The new advertised BC's for Berger bullets will be referenced to the G1 standard (same standard used for all other brands) and will represent the average BC from 3000 fps to 1500 fps, which covers the `typical' velocity range that our bullets operate at. Of course, some bullets will operate slightly above or below that band, and minor inaccuracies can be incurred because of that. I chose to use one average value for BC rather than defining it in velocity bands (like Sierra does) for a couple reasons. First of all, many shooters misunderstand the velocity bands, and simply apply the high velocity BC for the entire trajectory (perhaps thinking the BC is related to just the muzzle velocity). This will obviously cause inaccuracy in a trajectory prediction, and misrepresent the bullet when comparing it to others. Also, not all ballistic software programs have the ability to define multiple BC's.
Some Info on other brands BC's
Just for some context, not all bullet makers establish BC in the same way. Sierra test fires their bullets for BC, and reports different BC's for each velocity band. I've tested many Sierra bullets for BC, and with few exceptions, my tests have been in very good agreement with their claims (usually within +/- 3 to 5%). In order to make a fair comparison between Berger and Sierra bullet BC's, you have to average all of the Sierra BC's for each velocity band, and compare that to the single Berger BC. If you only compare the high velocity BC given by Sierra to the average Berger BC, it's not a true `apples-to-apples' comparison. I believe that both Hornady and Nosler also test fire their bullets for BC, however, their advertised values only apply for high velocity (tests are conducted only to 100 or 200 yards I think). This makes it hard to compare them to the Berger number. I'm not sure how Lapua calculates their BC's.
The effect of this change on 'Marketing'
We understand that slightly decreasing our advertised BC's may affect how `attractive' Berger bullets are to some customers who are impressed with high BC's alone. However, the amount that our advertised BC's are decreasing is so small that there are few cases where we change positions on the totem pole. In other words, if we had the highest BC before the change, we still probably have the highest BC, but maybe by a smaller margin. There's also the accuracy of the other brands advertised BC's to consider when looking at the totem pole.
To be honest, I've always hated the idea of BC being used as a marketing tool (although I can't deny that it can be effectively used as such). The BC of a bullet is an important number that people use to analyze the performance of rifles, calculate trajectories, and hit targets. I believe that our new BC's are more accurate, and will help shooters achieve better success which is what I think it's all about.
Future Plans
There are plans to improve the way we represent our BC's in the future that's less tied to velocity which will clear up a lot of the ambiguity on the subject. It will be a challenging transition, and we'll make it when we feel all the pieces are in place to give it the best chance of success. Until then, we feel that these experimentally determined, average G1 BC's are the best way to go.
I am happy to address any questions or concerns related to this change.
-Bryan
Ballistician
Berger Bullet
Comments
CC
The big changes will come when I get to drag everything out to NV to shoot. FWIW, I've found that Berger was pretty close and Sierra with their 'new ballistics' have been slightly under. But, my findings aren't exactly scientific. I start with an F1 Chrony and basically dial in then adjust for wind. Later on I compare it to JBM. Since my long range groups aren't super tight I then take averages. So far it's the Sierra's that've come up low for BC. They shoot better than the stats give them. Of course they always have been accurate from a close range perspective.
Mostly, this is an informative type of post which is meant to let shooters know what procedures have been used to establish BCs previously and how procedures have changed, at least for Berger.
I think most shooters assumed that the various bullet designs were 'shot in' by the manufacturers to establish the BC. With the increased costs and liability, virtually all of the manufacturers abandoned live fire testing ages ago, depending instead on highly refined ballistic programs to supply the data. They do a little live fire analysis but it is severely diminished from previous data collection. Many even use this process for their reloading sections on their websites also.
I haven't used printed BCs for many years simply because of the number of variables that affect this particular number for the individual shooter and his or her equipment. I buy a large number of bullets from one lot number (1,000 to 5,000 depending) and test them. If they don't match up to my standards, I sell them and look for the next bullet to test. The testing yields a drop chart as an end result which I use to continue the testing for other factors. But more critical to target shooters and precision hunters is how consistently they group and the shape of the group at the distances that are important to them.
Anyway, I thought it was good information and little change of pace for discussion.
Best.
How many people who wish to build a custom rifle dedicated to long range shooting have built an entire system around one bullet...only to have it fall short and then need to "pump up" their system with other quick fixes. Knowing the right characteristics of each bullet and what you will have to do to make it work right is such a good feeling when it's right from the get-go. So it is good information.
As a close aside from Berger's BC's What do you generally find with other 'Custom' makers bullets?
"As a close aside from Berger's BC's What do you generally find with other 'Custom' makers bullets?"
Nowadays, most of the Custom bullet BCs are reasonably close to what I derive when I shoot them in. Close is relative but it means that they have a starting place for me to use and I do the rest.
Most of the 'Custom' bullet makers use a design program and consultation with former bullet makers and component suppliers to arrive at a design. Then they wash the finished bullet dimensions through a ballistics program to get a basic idea of the potential BC. It's fast, easy and relatively inexpensive by comparison to the older ways.
Some of the Benchrest bullet makers invest a lot of time and effort into test shooting their bullets to have the actual real time BC. This stands to reason, seeing the profit potential that exists for many of them.
Other folks have suffered at the hands of some prima donna shooters and 'internet idiots' for releasing a limited amount of information about the BCs of their bullets, that those BCs are a suggested starting point and haven't been tested. Even when they state such a disclaimer about the lack of testing and that all rifles and loads are different, allowing for a variance in the resulting BCs, there have been accounts of piling on or hyena-type behavior by members of other forums. I know one bullet maker personally who simply stopped posting information at all and refused to deal with some members that wanted his product. He made a statement that none of his bullets had BCs and that it was up to the individual to establish such BCs as their equipment and loads delivered, which was what he meant in the first place. He went on to be very successful.
It really doesn't affect me since I run all my own tests. It costs me more money but I'm the one that's responsible for my equipment and shooting so it's part of the process.
Best.