New Hornady Bullets

[Balljoint]

Is anyone using OR got thair hands on these new bullets check this out http://bulletin.accurateshooter.com/2011/03/new-hornady-hpbt-match-bullets-most-have-arrived/

[calib]

i would like to maybe try some. i just put together my 7mm stw and wonder what those 162 grainers would do in it. the cost is a fraction of the 168 bergers. i also built a 243 ai and am wondering if those 6mm 105 grainers would work well in a 1:9 twist

[Varget 7-08]

Hmm, wonder what the BC is for the 140 6.5?

[Samdweezel05]

I would try the 105's.

[BoilerUP]

Hmm, wonder what the BC is for the 140 6.5?


0.580.

[Varget 7-08]

Hmm, wonder what the BC is for the 140 6.5?


0.580.


Oh that's kind of disappointing.

[BoilerUP]

Oh that's kind of disappointing.

I think its pretty good when you consider the 140gr MatchKing is 0.535, the Nosler Custom Comp is 0.529, and the 140 A-Max is 0.585.

[Varget 7-08]

Very true but the VLD is .595 and the Scenar's is .615, I just meant disappointing because it's a new bullet and doesn't offer a higher BC

[helotaxi]

I'd be more interested in the G7 BC. Unfortunately no one other than Berger lists that. It can be computed fairly closely, but I don't have the setup to do the measurements.

[rsbhunter]

helotaxi, in laymans terms, what is the difference between the G1 and G7 BC ? i have been seeing alot of these different types and thought i knew about BC until this??? Thanks, rsbhunter

[helotaxi]

The G1 BC is based on a reference projectile that is relatively short for caliber and has a flat base. What the ballistic coefficient represents is a scaling of that drag curve. The problem is that the G1 drag curve is not a very good match for boat-tailed bullets at lower velocities. At short range where the velocity is still pretty high, the difference isn't that significant. However, at longer range when the bullet begins to slow into the transonic region the difference is pretty big. Plenty big enough to reduce any drop calculations to worthless.

The G7 coefficient is based on a streamlined, boat-tailed, high efficiency projectile and provides a more accurate model in the transonic region. If you want more accurate predictions of performance, you need a model that better represents the situation. For long range bullets, the G7 is that better model. For flat based bullets, the G1 is still perfectly valid.

If you want a really informative read about the subject, Applied Ballistics for Long Range Shooting by Brian Litz is an excellent read. Powder Valley is one of the only places I ever found it in stock.

[MatthewUSMC8791]

The G1 BC is based on a reference projectile that is relatively short for caliber and has a flat base. What the ballistic coefficient represents is a scaling of that drag curve. The problem is that the G1 drag curve is not a very good match for boat-tailed bullets at lower velocities. At short range where the velocity is still pretty high, the difference isn't that significant. However, at longer range when the bullet begins to slow into the transonic region the difference is pretty big. Plenty big enough to reduce any drop calculations to worthless.

The G7 coefficient is based on a streamlined, boat-tailed, high efficiency projectile and provides a more accurate model in the transonic region. If you want more accurate predictions of performance, you need a model that better represents the situation. For long range bullets, the G7 is that better model. For flat based bullets, the G1 is still perfectly valid.

If you want a really informative read about the subject, Applied Ballistics for Long Range Shooting by Brian Litz is an excellent read. Powder Valley is one of the only places I ever found it in stock.







Absolutely a great book and now versin 2 is out shortly... G& is the way to go with a VLD type bullets...