March 16th, 2011

Tangent vs. Secant vs. Hybrid Ogive — Bryan Litz Explains

In discussions of ballistics, you’ll see references to “tangent” and “secant” bullet shapes. We know that, for many readers, these terms can be confusing. To add to the confusion, bullet makers don’t always identify their projectiles as secant or tangent designs. This article provides a basic explanation of tangent and secant designs, to help you understand the characteristics of both bullet shapes.

Tangent Ogive vs. Secant Ogive vs. Hybrid
Most match bullets produced today use a tangent ogive profile, but the modern VLD-style bullets employ a secant profile. To further complicate matters, the latest generation of “Hybrid” projectiles from Berger Bullets feature a blended secant + tangent profile to combine the best qualities of both nose shapes. The secant section provides reduced drag, while the tangent section makes the bullet easier to tune, i.e. less sensitive to seating depth position.

Berger Bullets ballistician Bryan Litz explains tangent and secant bullet ogive designs in a glossary section of his Applied Ballistics website, which we reprint below. Bryan then explains how tangent and secant profiles can be combined in a “hybrid” design.

How Bullet Ogive Curves are Defined
While the term “ogive” is often used to describe the particular point on the bullet where the curve reaches full bullet diameter, in fact the “ogive” properly refers to the entire curve of the bullet from the tip to the full-diameter straight section — the shank. Understanding then, that the ogive is a curve, how is that curve described?

LITZ: The ogive of a bullet is usually characterized by the length of its radius. This radius is often given in calibers instead of inches. For example, an 8 ogive 6mm bullet has an ogive that is a segment of a circular arc with a radius of 8*.243 = 1.952”. A .30-caliber bullet with an 8 ogive will be proportionally the same as the 8 ogive 6mm bullet, but the actual radius will be 2.464” for the .30 caliber bullet.

For a given nose length, if an ogive is perfectly tangent, it will have a very specific radius. Any radius longer than that will cause the ogive to be secant. Secant ogives can range from very mild (short radius) to very aggressive (long radius). The drag of a secant ogive is minimized when its radius is twice as long as a tangent ogive radius. In other words, if a tangent ogive has an 8 caliber radius, then the longest practical secant ogive radius is 16 calibers long for a given nose length.”

Secant Ogive vs. Tangent Ogive

tangent Secant Ogive

Ogive metrics, and Rt/R
LITZ: There is a number that’s used to quantify how secant an ogive is. The metric is known as the Rt/R ratio and it’s the ratio of the tangent ogive radius to the actual ogive radius for a given bullet. In the above example, the 16 caliber ogive would have an Rt/R ratio of 0.5. The number 0.5 is therefore the lowest practical value for the Rt/R ratio, and represents the minimum drag ogive for a given length. An ogive that’s perfectly tangent will have an Rt/R ratio of 1.0. Most ogives are in between an Rt/R of 1.0 and 0.5. The dimensioned drawings at the end of my Applied Ballistics book provide the bullets ogive radius in calibers, as well as the Rt/R ratio. In short, the Rt/R ratio is simply a measure of how secant an ogive is. 1.0 is not secant at all, 0.5 is as secant as it gets.

Hybrid Bullet Design — Best of Both Worlds?
Bryan Litz has been developing a number of modern “Hybrid” design bullets for Berger. The objective of Bryan’s design work has been to achieve a very low drag design that is also “not finicky”. Normal (non-hybrid) secant designs, such as the Berger 105gr VLD, deliver very impressive BC values, but the bullets can be sensitive to seating depth. Montana’s Tom Mousel has set world records with the Berger 105gr VLD in his 6mm Dasher, but he tells us “seating depth is critical to the best accuracy”. Tom says a change of .005″ in seating depth “can cause the group size to increase substantially”. In an effort to produce more forgiving high-BC bullets, Bryan Litz has developed a hybrid tangent/secant bullet shape. This is explained in the illustration below.

hybrid bullet

Story sourced by Edlongrange.
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March 16th, 2011

Superstar Lady Shooters Featured on Outdoor Channel Tonight

Julie GolobTonight, on the Outdoor Channel, you can watch four of America’s best female action and multi-gun shooters. In tonight’s episode of the Shooting Gallery on the Outdoor Channel, ace USPSA shooters Julie Golob, Tasha Hanish, Lisa Munson, and Randi Rogers show off their skills with pistols, rifles, and shotguns. Golob, captain of Team Smith & Wesson, is a National Champion Pistol Shooter who is now taking up the multi-gun challenge. Hanish, one of the top shooters for Team FNH, is a two-time USPSA Multi-Gun National Champion (Women’s Tactical Division). Lisa Munson has captured 11 National Pistol titles over the years, and now competes with Team Smith & Wesson, along with Golob. Randi Rogers (aka ‘Holy Terror’) is a multi-time Cowboy Action Ladies World Champion who has been shooting modern pistols with Team Glock for the past few years. Randi has won numerous tournaments for Glock. If you ever get a chance to watch Randi shoot a lever gun (from her cowboy action days) — you will be amazed. In speed events, using her lever gun, she could beat most male competitors who are using modern semi-auto rifles. She is that fast and accurate.

Preview Tonight’s Shooting Gallery Episode
Here is a preview from Tonight’s Shooting Gallery, hosted by Michael Bane.
Outdoor Channel Airtimes are: 03-16-11 at 3:30pm, 7:00pm, 9:00pm | 03-17-11 at 3:00am.

Tasha Hanish at Multi-Gun Nationals — You Go, Girl!
In the following video, taken at the 2010 USPSA Multi-Gun Nationals, you can see Tasha Hanish blaze through a 3-gun stage. Tasha starts with her 9mm pistol, then grabs her shotgun to blast steel plates, and finally engages a bank of 200-yard targets with her FNH SCAR rifle. Tasha won the Ladies’ 2010 Multi-Gun Championship in the Tactical Class.

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March 16th, 2011

Earn Bucks Blogging for Beretta as “Social Media Manager”

Beretta media jobHere’s the perfect part-time job for a web-savvy gun aficionado. Berreta is seeking a free-lance Social Media Manager to work with gun blogs, gun forums, Facebook, Twitter, MySpace and other social media outlets on the internet. Beretta’s Social Media Manager will be tasked with promoting Beretta’s products and direct-marketing initiatives through non-traditional digital media. What does that mean? Well, you’ll send press releases to sites like this one, you’ll update Beretta’s facebook page regularly, and you’ll monitor gun forums to “spread the word” about Beretta firearms and sporting products.

We think Beretta is smart to utilize modern digital media to deliver its marketing message. Here are the specific job requirements:

Beretta Social Media Manager Position

ESSENTIAL JOB FUNCTIONS: Work with Marketing team to take existing collateral and promote it on all applicable social networking touch points. Ensure social media tools are kept up to date. Manage social media campaigns and daily activities to include: on-line advocacy, writing editorial, consumer-outreach efforts and promotions. Be an advocate of Beretta in social media spaces, engaging in dialogue and answering questions. Manage presence in social networking sites including Facebook, Twitter, and other similar community sites, posting on relevant blogs, and seeding content where applicable. Monitor trends in social media tools.

MINIMUM JOB REQUIREMENTS:
• Bachelor’s degree in Business Administration, Marketing, or related field, or combination of education and related work experience.
• Minimum of 5 years experience representing a recognized brand.
• Knowledge of Beretta products and services required.
• Advanced pc skills including Microsoft Office/Internet.
• Ability to troubleshoot pc-related technical problems.
• Strong command of the English language.
• Attention to detail and accuracy required.

By the way, Beretta is also looking for a new Shotgun/Rifle Marketing Manager. To apply for either position, log on to Beretta’s Career Opportunities Webpage and click on the Online Resume Link. You can also mail your resume and cover letter to:

Beretta USA Corp:
Attn: Human Resources
17601 Beretta Drive
Accokeek, MD 20607

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