Michael Courtney
Silver Member
For those unfamiliar with our work, for the last decade, my colleagues and I have published more scientific work in external ballistics than most other researchers in the US, except perhaps for those directly affiliated with bullet companies. I've published papers (with Don Miller) where we improved the original Miller formula to more accurately compute stability for plastic tipped bullets, including using BC measurements to accurately detect the onset of instability as drag is lowered from 1.2 to 1.0. This improved twist formula has been incorporated into several ballistics calculators, including JMB and Patagonia's Cold Bore. After Don passed, colleagues and I used this new experimental method to modify the stability formula to more accurately treat open tipped jacketed rifle bullets.
We've also developed relatively inexpensive methods (<$1000) to quantify the drag effects of pitch and yaw and the damping of pitch and yaw in flight. This allows both military and civilian shooters to see how pitch and yaw are affecting the drag of any bullet of interest without much more expensive techniques like time on the ARL spark range or radar. We've published several papers evaluating the accuracy of manufacturer's BC specifications, and past publications have focused on the significant inaccuracies of some vendors like Nosler, as well as the smaller inaccuracies of other vendors.
Our first experience with inaccurate BCs from Berger came in 2005/2006 when we had a VLD fail to expand on a 550 yard shot on a deer. We'd corrected the scope adjustment for the actual measured drops at long ranges, but we trusted the published BC value when computing impact velocity and energy. The deer was found a few days later, center punched through both lungs by a bullet that penciled through. We'd developed methods for measuring BCs because we needed to accurately assess pistol bullet BCs for our studies of terminal performance in deer. Measuring the VLD BC yielded a number that was 20% below Berger's published value.
Shortly after that, Berger hired Bryan and the BC of the 115 grain .257 VLD was revised downward from .523 to .466. After some exchanges with Bryan, the BC of 0.419 was attributed to dimensional variations from worn dies, and Berger sent us new bullets. Measuring the BCs of the new bullets showed that they were within spec, and we were aware that Berger had adjusted their BCs to Bryan's fired values. We went on our merry way believing that we could trust the accuracy of all of Berger's published BCs.
Over time, our relationship with the DoD grew closer, and various DoD parties became more interested in fielding more commercial off the shelf products (COTS). These interests have led to lots of product testing on our part. In addition to publishing info related to various companies who seem to be exaggerating their published BCs, we've published material showing how unreliable lead free primers are, how much lot to lot variations Hodgdon Extreme powders really have, how bad some lead free bullets are, measuring bullet friction and effects of bullet coatings on friction, and also testing terminal performance of several .30 caliber bullets at low impact velocities. We've also tested lots of products to better inform our methods and theoretical models by using a wide array of products in test cases rather than limiting ourselves to military components.
Having experienced the accuracy of Berger bullets, our attention was drawn to their 62 grain flat base .224 bullet for several reasons. At the same weight and nearly the same advertised BC (0.291) as the M855, loads could be developed that were the ballistic equivalent. We expected it to be a more accurate and more precisely manufactured bullet (it is), which would make for interesting comparisons in things like bore friction, stability, pitch and yaw, etc. We also became interested in the 52 grain Berger flat base bullet as an accurate bullet as an additional test case for the new methods and formulas being developed. Given the much publicized revision of Berger BCs that had occurred in 2009 we had no cause to doubt the accuracy of the published specs.
We were surprised when BC testing showed both bullets to be significantly lower than Berger's spec, with the 62 grain varmint bullet 16% low (0.245) and the 52 grain bullet 8% low (0.179). We'd spent hundreds of dollars on bullets, thousands on rifles and equipment, and invested hundreds of man hours on these and some other bullets that were needed for various projects. Fortunately, the news broke on the 300 grain .338 bullet failing to meet its spec before we invested in an expensive .338 Lapua for a wind drift project. As usual, Berger bullets always showed impressive accuracy and drop could be corrected with simple scope adjustments, but wind drift was greater, terminal velocity was lower, and lower BC bullets have their sonic transition at a shorter range.
When Berger was informed about the lower BCs of these varmint bullets, they refused to directly answer the question about whether these BCs have actually be measured in firing tests or whether the published BCs were based on a theoretical model. This was surprising because in 2009 Eric Stecker had asserted that BCs of the whole product line were being revised "to Bryan's fired numbers." After they refused to directly answer our inquiry about whether these two BCs were actually measured, we reviewed the history of their published BCs and produced the above graph showing that apparently 30 or 31 of the 66 revised BCs do not seem to have been measured.
In the same way that product problems with Ford SUVs may not directly impact Ford truck drivers, Berger's misstating specs for their flatbase varmint and target bullets may not directly impact shooters of their boat tail bullets. But honest drivers of Ford trucks would say that Ford owes SUV owners honest specifications on things like horsepower and gas mileage. Treating customers right and well with the best available specifications for some products does not really help the customers of the products who are being misled regarding product specifications.
Much earlier in my career, I worked as an engineer for a couple of companies in roles closely related to product specifications. These companies faced ongoing temptation to rationalize that certain product specs weren't really important to most customers, even though they were clearly advertised in marketing materials. I always had tremendous zeal to ensure our products met all the marketing specs. I resigned from one company who refused to be honest with our customers. At another company, I insisted that factory tests be implemented that ensured all our products met the advertised specs. As the senior engineer responsible for both design validation and factory tests, my refrain was "fix the product, not the tests" when other engineers and management approached and requested that the tests be modified to pass and ship defective product. I've always defined defective product as product not meeting the marketing specs.
I still carry this zeal for customer advocacy and product quality with me today. Products that are marketed to DoD, law enforcement, and the shooting public should meet their marketing specs. While this is obvious for things like ballistic helmets and vests, we believe it also applies to ammunition and components. Would having the best available ballistic helmet justify basing the minimum penetration velocity spec of a 9mm bullet on a theoretical value that was 100 ft/s higher than what was later obtained by an independent party in actual testing?
We've also developed relatively inexpensive methods (<$1000) to quantify the drag effects of pitch and yaw and the damping of pitch and yaw in flight. This allows both military and civilian shooters to see how pitch and yaw are affecting the drag of any bullet of interest without much more expensive techniques like time on the ARL spark range or radar. We've published several papers evaluating the accuracy of manufacturer's BC specifications, and past publications have focused on the significant inaccuracies of some vendors like Nosler, as well as the smaller inaccuracies of other vendors.
Our first experience with inaccurate BCs from Berger came in 2005/2006 when we had a VLD fail to expand on a 550 yard shot on a deer. We'd corrected the scope adjustment for the actual measured drops at long ranges, but we trusted the published BC value when computing impact velocity and energy. The deer was found a few days later, center punched through both lungs by a bullet that penciled through. We'd developed methods for measuring BCs because we needed to accurately assess pistol bullet BCs for our studies of terminal performance in deer. Measuring the VLD BC yielded a number that was 20% below Berger's published value.
Shortly after that, Berger hired Bryan and the BC of the 115 grain .257 VLD was revised downward from .523 to .466. After some exchanges with Bryan, the BC of 0.419 was attributed to dimensional variations from worn dies, and Berger sent us new bullets. Measuring the BCs of the new bullets showed that they were within spec, and we were aware that Berger had adjusted their BCs to Bryan's fired values. We went on our merry way believing that we could trust the accuracy of all of Berger's published BCs.
Over time, our relationship with the DoD grew closer, and various DoD parties became more interested in fielding more commercial off the shelf products (COTS). These interests have led to lots of product testing on our part. In addition to publishing info related to various companies who seem to be exaggerating their published BCs, we've published material showing how unreliable lead free primers are, how much lot to lot variations Hodgdon Extreme powders really have, how bad some lead free bullets are, measuring bullet friction and effects of bullet coatings on friction, and also testing terminal performance of several .30 caliber bullets at low impact velocities. We've also tested lots of products to better inform our methods and theoretical models by using a wide array of products in test cases rather than limiting ourselves to military components.
Having experienced the accuracy of Berger bullets, our attention was drawn to their 62 grain flat base .224 bullet for several reasons. At the same weight and nearly the same advertised BC (0.291) as the M855, loads could be developed that were the ballistic equivalent. We expected it to be a more accurate and more precisely manufactured bullet (it is), which would make for interesting comparisons in things like bore friction, stability, pitch and yaw, etc. We also became interested in the 52 grain Berger flat base bullet as an accurate bullet as an additional test case for the new methods and formulas being developed. Given the much publicized revision of Berger BCs that had occurred in 2009 we had no cause to doubt the accuracy of the published specs.
We were surprised when BC testing showed both bullets to be significantly lower than Berger's spec, with the 62 grain varmint bullet 16% low (0.245) and the 52 grain bullet 8% low (0.179). We'd spent hundreds of dollars on bullets, thousands on rifles and equipment, and invested hundreds of man hours on these and some other bullets that were needed for various projects. Fortunately, the news broke on the 300 grain .338 bullet failing to meet its spec before we invested in an expensive .338 Lapua for a wind drift project. As usual, Berger bullets always showed impressive accuracy and drop could be corrected with simple scope adjustments, but wind drift was greater, terminal velocity was lower, and lower BC bullets have their sonic transition at a shorter range.
When Berger was informed about the lower BCs of these varmint bullets, they refused to directly answer the question about whether these BCs have actually be measured in firing tests or whether the published BCs were based on a theoretical model. This was surprising because in 2009 Eric Stecker had asserted that BCs of the whole product line were being revised "to Bryan's fired numbers." After they refused to directly answer our inquiry about whether these two BCs were actually measured, we reviewed the history of their published BCs and produced the above graph showing that apparently 30 or 31 of the 66 revised BCs do not seem to have been measured.
In the same way that product problems with Ford SUVs may not directly impact Ford truck drivers, Berger's misstating specs for their flatbase varmint and target bullets may not directly impact shooters of their boat tail bullets. But honest drivers of Ford trucks would say that Ford owes SUV owners honest specifications on things like horsepower and gas mileage. Treating customers right and well with the best available specifications for some products does not really help the customers of the products who are being misled regarding product specifications.
Much earlier in my career, I worked as an engineer for a couple of companies in roles closely related to product specifications. These companies faced ongoing temptation to rationalize that certain product specs weren't really important to most customers, even though they were clearly advertised in marketing materials. I always had tremendous zeal to ensure our products met all the marketing specs. I resigned from one company who refused to be honest with our customers. At another company, I insisted that factory tests be implemented that ensured all our products met the advertised specs. As the senior engineer responsible for both design validation and factory tests, my refrain was "fix the product, not the tests" when other engineers and management approached and requested that the tests be modified to pass and ship defective product. I've always defined defective product as product not meeting the marketing specs.
I still carry this zeal for customer advocacy and product quality with me today. Products that are marketed to DoD, law enforcement, and the shooting public should meet their marketing specs. While this is obvious for things like ballistic helmets and vests, we believe it also applies to ammunition and components. Would having the best available ballistic helmet justify basing the minimum penetration velocity spec of a 9mm bullet on a theoretical value that was 100 ft/s higher than what was later obtained by an independent party in actual testing?
lightbulblightbulblightbulb.STAY ON IT.
