.223 Hornady A-tip 90 gr., anybody?

[taliv]

For the 90 second version read this article
https://bergerbullets.com/berger-bul...er-bryan-litz/

Basically he contends that just because you twist fast enough to make round holes doesn’t mean you’re achieving max BC.

Benchrest conventional wisdom was often that you wanted to spin the bullet just fast enough to poke a round hole and no more because accuracy. But litz is saying ok you may be accurate but your bc is less than it could be by spinning it faster. So they built a calculator and put it on Berger’s website some years ago.

[taliv]

As an aside that’s when I started ordering gain twists from bartlein starting at the minimum twist and speeding up to litz optimal twist.

No good reason. It just sounded cool. I stopped doing that when impact started the pre-fit craze

[markm]

Basically he contends that just because you twist fast enough to make round holes doesn’t mean you’re achieving max BC.

That's pretty interesting. But I'm the reloader who NEVER knows the B.C. of any bullet because I literally do not care.

I mean... A nice B.C. is fine, but I'm more interested in the quality and consistency of the bullet. These 90s are probably the best made bullets we'll ever shoot in .223/5.56, but are ridiculously expensive for regular consumption.

I am curious to see the length of both these bullets and the 87 gr Barnes side by side. The 87 looked like a 77 in our buddy's pic.

Due to 116 degree temps this weekend, we won't be shooting any test loads.

[taliv]

i think we're saying basically the same thing. consistency is king. the problem isn't just "max bc" but rather the correct bc. that is, most people enter the bc and velocity in their calculator and then scratch their head when their dope doesn't line up at distance, and wonder if their chrono isn't calibrated or the mfg lied about the bc or maybe their scope isn't tracking. litz is saying maybe you're not spinning the bullet fast enough to achieve the published bc.

[markm]

Ahhh.. I gotcha.

That would explain the guys who claim the B.C. isn't exactly right on the box/from the manufacturor.

The spin thing IS pretty interesting. I'd never given that thought in the B.C. context.

[taliv]

Sorry dupe

[taliv]

Yep

So what struck me as odd was that if I remember correctly when Sierra came out with their 90g that were popular in high power where you were required to single feed them anyway, I thought their box said 1-6.5 twist.

Attachment 63085

It just made me wonder if Sierra and Berger are more aggressive than Hornady in their twist recommendations.

[markm]

Yeesh. These are LONG bullets. From L to R 90, 80, and 77 gr.

[markm]

No chance of a safe round in mag length. There'd barely be any neck tension at the base of the neck. The shiny reflection on the bullet is the bearing surface and where the neck needs to hold onto it.

[markm]