Revised BC Assessment
For unknown reasons, the original BC test produced results that were not repeatable for this bullet. Upon releasing these bullets to the public, we started to hear that trajectories predicted with the advertised BC’s were not matching the observed drop. We took this feedback seriously, and performed several more careful BC tests. The results of each of these tests have produced a repeatable BC, but it’s lower than the original value by about 7%.

The revised BC’s for the 300 grain .338 Hybrid are:
G7 BC = 0.419
G1 BC = 0.818

The above BC’s have been measured in multiple tests in multiple barrels, and produce calculated trajectories that match the observations of some credible shooters.

We’re grateful for the feedback of the shooters who brought this matter to our attention and allowed us to correct the inaccurate information. Greater care will be taken with future tests in an effort to prevent this from happening again.

Limitations to the Bullet’s Structural Integrity
Another thing that happened when we released these bullets to the public is that they were fired in cartridges that are more energetic than the .338 Edge which I used for the initial evaluations. Upon exposure to the extreme pressures and accelerations produced by some of the larger cartridges, some negative results were observed; poor groups, and lower observed BC (even lower than the revised values above). Our current working theory is that the poor precision and reduced BC are a result of nose slump. Nose slump is when the bullet is accelerated so fast that the base of the nose can’t support its own weight, and bulges out to fill the barrel. This produces a bullet with a longer bearing surface and a shorter nose which explains the compromised BC. Since this deformation doesn’t occur exactly the same every time, poor precision also results.

The exact threshold of pressure/acceleration that will cause nose slump with this bullet is not known. There are a number of small to medium capacity cartridges that shoot these bullets very well, with extremely good precision and a repeatable BC. So far there have been no reported cases of nose slump with cartridges in the following class: .338 Winchester Mag, .338 Norma Mag, .338 RUM, and .338 Edge, etc.

The .338 Lapua Mag seems to be a borderline case which may or may not produce nose slump. Factors that affect pressure/acceleration will affect the likeliness of nose slump occurring. For example, ball powders are typically faster burning than stick powders, so they produce higher peak pressures, and are more likely to produce nose slump. Tighter bores can also cause elevated pressures and tip the scales toward nose slump.

Cartridges like the .338 Lapua Mag Improved and larger are virtually assured of producing nose slump when loaded to their potential pressures.

If you’re working up a load with these bullets and having difficulty finding a precise load, it’s likely that you’re exceeding the pressure threshold where nose slump happens. In small to medium cartridges, the hybrid ogive design makes it quite easy to find an accurate load. The bullet is quite insensitive to seating depth. If you’re working with a large capacity case and having poor results, you should consider reducing the powder charge until good groups are achieved.

When designing a bullet for use in hunting applications, the toughness of the bullet is always a trade-off. Terminally, you want a bullet that is capable of reliable expansion/fragmentation at low impact velocities. However, the bullet can’t be so thin-skinned that it doesn’t survive being launched at very high speeds. This being our first time working with a bullet this large, a construction was selected which we felt would strike the best balance between toughness and terminal performance. Simply put, we erred too much on the side of terminal performance. The result is a bullet that’s perfectly suited for small to medium capacity cases, but simply isn’t tough enough to survive being fired from the more energetic magnums.

The good news is that the situation has been identified and several solutions are already being worked on. We know the design needs to be ‘toughened up’ for successful use in larger cartridges, and we’re considering the best way to do this.

In Summary
The Berger .338 caliber 300 grain Hybrid bullet is still the highest BC bullet in its class. The performance gap just isn’t as big as originally thought.

In its current form, the bullet is perfectly suitable for many popular small to medium capacity cartridges. From my .338 Edge test rifle, I’ve shot multiple 10 shot groups at 1000 yards under 10” and the bullets performed with a very repeatable BC. For the time being, those with larger capacity cartridges will have to wait for the bullet to be toughened up in order to achieve good performance. We don’t have an anticipated timeline for this revision, but it is a top priority.

On a personal note, I want to express my gratitude for the shooters who’ve provided the critical feedback which helped us to understand the situation enough to take action. Having an open dialogue and exchange of information is the best way to ensure we’re doing everything we can to make the best bullets possible.

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This 3.048″ 10-shot group was a remarkable accomplishment, breaking one of the longest standing 1000-yard World Records. Bill Shehane commented: “This tops the NBRSA, IBS, and Original Williamsport Clubs’ all-time 10-shot Heavy Gun group records. Took a long time to do it and I for one know Joel did not back into it — he has worked harder than most the last 10 years to break this record. And just like John Voneida of the Original Williamsport Club who held this most prestigious record for so long, Joel is a super nice guy and a great competitor.”

Pendergraft’s fellow 1K competitors were quick to praise his accomplishment. Dave Tooley observed: “I still remember the day I suggested flat-based bullets to Joel and the laugh I got. Well he was laughing today. Couldn’t have happened to a nicer guy. Glad I was there to see it.” Posting on Benchrest Central, “4Mesh” wrote: “Couldn’t happen to a nicer guy! That gun showed some serious promise last year at the World Open and anything that cranks off targets like the one you shot there, has what it takes.” Jim Hardy added: “The new record is great but no better than the fine man who shot it. Everyone who knows Joel will say the same thing — he is one of the finest men you will ever meet. He lives the life, and walks the walk and has paid his dues in the 1000-yard BR game to get the record.”

Pendergraft was modest after his notable achievement: “Some of the words spoken are too kind. What makes this so very special is to be able to celebrate the accomplishment with all of my shooting friends[.] A good friend once said that records are shot when preparation and opportunity meet. I feel blessed to have personally had the opportunity. The preparation we can individually work on and achieve but the opportunity only comes to a few. Those of you that compete in long range competition will know what I mean.”

Very-low-drag bullets (VLD) were primarily a small arms ballistics development of the 1980s–1990s, driven by shooters’ desire for bullets that will give a higher degree of accuracy and kinetic efficiency, especially at extended ranges. To achieve this, the projectile must minimize air resistance in flight. Demand has been greatest from Long Range Target shooters, including benchrest competitors, but hunters have also benefited. Most VLD bullets used today are in rifles.

By increasing the bullet’s ballistic coefficiency, the bullet decelerates less rapidly or stays super sonic longer. This in turn flattens the projectile’s trajectory some what, markedly decreases the lateral drift caused by crosswinds. and the higher resultant velocity at impact thus delivers more kinetic energy. This is called more “Smack Down”…LOL

The development of VLD bullets has focused on the following main factors:

1: The production of bullets with concentric and coincident centers of form and centres of mass.
2: Bullet design incorporating a secant ogive, tangent ogive, Von Kármán ogive or Sears-Haack profile in the bullet’s nose area.
3: The use of carefully tapered bullet heels, or boat-tails.
4: A cavity or hollow in the bullet nose (hollow point) to shift the projectile’s centre of gravity rearwards.

The resulting projectile is very “slippery” (well streamlined) for easier passage through the air. Consistency in bullet production, allied to consistency in the assembly of cartridges (quality control) should give excellent shot-to-shot consistency and repeatable accuracy.

The principles of bullet design and bullet flight are classically set out in Mann, F.W.: The Bullet’s Flight from Powder to Target: Ballistics of Small Arms (1942 and other reprints).

Producing consistantly accurate bullets this way is not easy. To guarantee consistency and thus accuracy, professional quality control during and after production is mandatory.

When Mike fired the first 200gr round, he thought he felt some blow back in his face. But after a thorough inspection of the rifle and 200gr ammo by Mike and one of the others, it seemed fine. On the second round the gun blew up in his face. I was not there when this happened but after talking to Mike and the details about what had happened it sounds like the 200gr bullet was accidentially charged with 2 grains more then the 180gr loads were. You see, when you are loading your own ammo, the heavier the bullet, the smaller the powder charge needs to be because of the chamber pressure. So, when you step up from the 180gr to a 200gr bullet, you actually step down in powder used…..not up as these were.

This is an example of the great care that needs to be taken when reloading. Check your work and then double check. If you are ever interupted while loading…stop and then start over when you come back. There are some serious consequences if even one step is missed and possibly death. Not only is there a risk of injury to you but people around you as well. You can imagine how you might feel if your lack of care, or an oversight perhaps on your part, caused someone to get hurt or killed! Any way, it looks like Mike will be fine. He has about 300+ pieces of copper/brass shavings in his right eye. But with care he should be back to normal in several weeks.

So I would like to ask everybody to pray for Mike and his family. Pray that the healing will be fast and painless and that his family stays strong knowing that someone far larger than you and I is in control.

TIPS

When stirring the gel, stir it slowly to reduce the air bubbles.
Try to keep the mixture flat in the refrigerator, so when it gels over, it will be a flat surface.
When melting the gel, just leave it on the stove long enough to melt. Letting it sit too long will boil away some water.

WARNINGS

When melting the gel, do not turn the stove up high, because boiling it will make it turn out bad. The highest the stove should be on, is medium low, or 2-3.

The above steps are for recreational creation of ballistics gel and not for scientific use.
Never fire a weapon unless you are trained to do so and you’re in an environment appropriately designated for weapons use.

Use extreme caution when using ballistics gel to test penetration of foreign objects. If it can damage the gel, it can kill.