tangent ogive vs secant ogive

[cjmac]

So im thinking tryin some hornady match in my 223. I was using sierra matchking, i know hornady bullets have a secant ogive . But will thay be hard to tune for finding a good OAL ?

 

[Warren Dean]

If they are a secant, AKA VLD, design, then yes...they might be a bit finicky.

Shoot 'em and find out. only YOUR barrel knows for sure.

 

[watercam]

I was under the impression that the Hornady's were a conventional, Matchking-like, profile.

 

[Sugar]

The Hornady match and SMK are definitely different. I have a 700 P that shoots both of them equally well but there is a significant difference in seating depth. If you set both bullets beside each other you can see the difference.

 

[dkhunt14]

I though they were tangent but they list them as secant. That all depends on your throat or barrel. I shoot VLDS in for best accuracy but some guys say they are really jumping them. You just have to try them both ways and see. If they don't shoot at a little off don't be afraid to really jump them. Matt

 

[CharlieNC]

Are you talking about the BTHP match, or the Amax; they are quite different.

 

[cjmac]

No not amax..the 68 gr BTHP and 53gr flatbase

 

[cjmac]

Good info.. hornady bullets are almost at every gun shop around here and thay are cheap. 16$ for box of 100 . My chamber is a match chamber ist pretty tight. I shoot there pistol bullets in my 1911 and ruger 44 mag....

 

[waldo1979]

I've had great luck with 75gr HPBT (tangent ogive) and terrible luck with the amax (secant ogive). Secant ogive are very sensitive to overall length and may like to be hard jammed. Frankly I don't have the patience to tune them on an AR platform (same with Berger VLDs).

I like bullets that can be jumped, I.e. Have a more durable jacket. I load the hornadys with somewhere around 0.025" jump but still shoot good at magazine lengths.

Picking the right weight bullet is a matter of how far you plan to shoot. 300 yard, 75gr. 100 yards, 50gr Z-max , aka zombies. I use benchmark for the lighter bullets and N135/varget/R15/H4895 for the 75gr hornadys or Sierra 80gr.

Hornady 75gr also shoot really well out of a 1:9 twist even though they're a bit heavy.

 

[Warren Dean]

Easy to identify the difference

Secants make a sharp transition from full diameter to the taper. Tangents make a more subtle transition...think Sierra SMK.

Looking at the cutaway of the Hornady bullet shows the secant characteristic of a sharp transition.

That sharp transition means that the diameter of the nose changes very rapidly in relation to the leade as it is moved forward, making them a bit finicky. That is the price you pay for the better ballistic coefficient of the secant ogive.

The tangents have a smoother transition without the finicky nature of the secant. However they give up a little in BC.

The Berger Juggernaut and, I believe, all the hybrids from Berger start out with a tangent ogive for a small distance and then transition to a secant ogive for better BC. That's probably why they shoot so well and are so popular.

If I told any of this wrong, please correct me, Bryan.

 

[ireload2]

It kind of depends on the leade in angle of your throat and the neck diameter of your chamber.
You will never know until you test them.

some of the best groups I have ever shot were with factory RN bullets of no particular ogive.

 

[cjmac]

Humm.. ..thay are a little cheaper also

 

[amlevin]

I absolutely love the 75 gr A-max. They perform or better than any other, more expensive, bullet I've sent down the barrel of my .223. In my rifle they seem to like a "head start" and best performance is at -.040" but my chamber has a nice snug freebore.

I also like the Hornady 80 gr A-Max but have found them a little harder to find. The A-max's are also very economical.

 

[r bose]

I've found that because of the design difference, I can add 1 full grain of powder more behind a 75g HPBT hornady than a 77 sierra both at mag length. Thus, pushing them faster thru the same barrel.

 

[John O.]

Is the firearm in question a bolt gun or a semi automatic?

 

[r bose]

Either bolt or semi auto actions. I like using TAC, and Ramshots load data manual shows the difference in powder charges also due to bullet design.