It was greek to me.......could someone kindly translate.....

[Savage Fanatic]

I had been talking to a smith in North Carolina whom is into the "custom gun" market.

The rifle I have been conversing with him in regards to is a far cry from "custom" In fact if I could bare the financial burden I would take it on a one way dog walk.

After explaining to him the issues I have been having with this particular rifle, and asking his opinion in regards to others. I took his word of advise and asked for his opinion in regards to having this rifle re barreled.

In a response to re barreling he stated:

If you are shooting Secant bullets, throat it for a .070-.100 jump. If you are shooting tangent bullets, shoot it touching the rifling.

In general I am able to grasp what he is stating but as to what he means per Secant bullets and Tangent bullets, put me out of his ball park.

Would some one here have better knowledge at what he is stating. And what one would need to look for to define Secant Bullets and Tangent Bullets. I am sure some background in Trigonometry, or Geometry would help

 

[Guest]

I can tell you that what he is referring to is the shape of the ogive of the bullet. There are basically two common types, secant ogive bullets, and tangent ogive bullets. You can check with the manufacturer to determine what the bullets you're using are. I know Barnes used to use a secant ogive, but they have recently gone to a tangent ogive. Hornady uses a secant ogive, I believe, but don't quote me on that. In fact, I may have the Barnes thing backwards, too, so check with whomever manufactured your bullets to determine their ogive shape. It is a complicated (or at least too complicated for me) concept of how the shape of the ogive is, related to the overall geometry of the bullet. I know that's awful ambiguous, but that's about as close as I can get.

I am curious as to what type of trouble you are having, and what kind of gun you're having it with. Please expound on the subject.

 

[Ol` Joe]

He is refering to the ogive geometery. The Secant shape is what Hornady uses on their bullets, more "pencil" shaped then curved. Nosler, Sierra, Speer, ect have a tangent ogive.

 

[Savage Fanatic]

Secant shape is what Hornady uses on their bullets, more "pencil" shaped then curved.

Basicly, or in terms of being asinine (me). Cone shaped. As the shape some of the first Barnes X's had.

Nosler, Sierra, Speer, ect have a tangent ogive.

And as stated above by yours truly. Tangent is refering to the shape most HPBT's have.

 

[Desert Fox]

Here's a simple explanation:

There are two basic types of ogival nose shapes: the tangent ogive and the secant ogive. A tangent ogive has an arc which meets the body contour smoothly, thereby creating no break in line where the ogive joins the cylindrical body. In other words, the center of rotation of the arc is in the plane of the base of the nose. If the center of rotation of the arc is aft of the plane of the base of the nose, you’ve got a secant ogive.

A good example of the tangent ogive bullet is the Ballistic Tip and the Hornady SST is an example of a secant ogive bullet.

 

[Savage Fanatic]

Here's a simple explanation:

There are two basic types of ogival nose shapes: the tangent ogive and the secant ogive. A tangent ogive has an arc which meets the body contour smoothly, thereby creating no break in line where the ogive joins the cylindrical body. In other words, the center of rotation of the arc is in the plane of the base of the nose. If the center of rotation of the arc is aft of the plane of the base of the nose, you’ve got a secant ogive.

A good example of the tangent ogive bullet is the Ballistic Tip and the Hornady SST is an example of a secant ogive bullet.

So, basicly if there is no "breaking line" in the arc at the base of the ogive then it is considered a Tangent ogive.

And if there is a "breaking line" in the arc at the base of the ogive then it is secant.

 

[FOTIS]

Being Greek this made sense to me! :lol:

 

[JD338]

Being Greek this made sense to me! :lol:

+1

JD338

 

[longwinters]

Yep, I learned something new here. Always knew that the two types of bullets shot better with different o-gives. But never thought of them having a name .

Like a buddy of mine once said . . . " I may be slow but I do poor work". For me I guess it would be " I know what they look like but don't know what they're called". Yep, really inspires confidence. :lol:

Long

 

[Savage Fanatic]

Like a buddy of mine once said . . . " I may be slow but I do poor work". For me I guess it would be " I know what they look like but don't know what they're called". Yep, really inspires confidence. :lol:

Long

Your not alone. I knew that there were geometrical measurements called tangent, secant, etc. But as to how they related to reloading, bullets, and re barreling. :?:

Many use "Hornady" products as example. For ten years I have been reloading I have never use Hornady bullets, nothing but Nosler here . I started out with their single stage press but after the third time of breaking out the ring groove in the link pins they wouldn't honor their warranty. That is when the press went in the garbage, and I have never looked back.

 

[matts318]

So which type of ogive is better for accuracy? Or which type is better for flatter trajectory? This has got me really curious, can somebody fill me in on what the performance difference is between the 2?

 

[Guy Miner]

In my experience, the tangent ogive bullets are easier to work with. It's not generally too hard to get an accurate load with them. The Secant ogive bullets on the other hand, such as the Berger VLD design, may take some fiddling to produce top accuracy. The advantage is that they generally have a very low BC, and shoot particularly well at long range.

Both types shoot well, the tangent ogive tends to be more forgiving.

Regards, Guy

 

[Desert Fox]

Secant ogive bullet should be seated closer or better yet, touch the land to shoot accurately. On average, it has higher B.C's than a tangent ogive bullet of the same weight. Which design is more superior? that's for the individual shooter to decide. I get better accuracy with most of my rifles using Hornady bullets, which are of secant ogive design. On the other hand, my 308 Tactical Rifle shoots better with Nosler 168 Comp match bullet with Tangent ogive nose. Why?, that's because the gunsmith used the reamer that is design for the 168 grain Sierra MK, which is almost the mirror image of the Nosler Comp bullet.