The Berger twist rate calculater shows the 180 .288” Woodleigh bullet (.513 B.C.) to be “marginally stabilized”
at 2500fps from a .270 1-10 twist rate.
You rely on a hypothetical Berger calculator instead of what Woodleigh the designer/manufacturer tested in the real world?
do you feel like contacting WL to tell them about what the Berger calculator tells you?
btw: achievable velocities are closer to 2700 fps
Re: "marginal stability"
For shorter ranges, marginal stability isn’t really an issue,( especially a high borerline case 180 WL stability factor of 1.45)
A marginal stability project. can still travel with good accuracy and precision, even though BC performance is less than ideal.
people interested in max. LR performance would need a slightly better twist to fully stabilise a projectile for best BC performance...
which is not imperative for the vast majority of hunters.
your Berger calc gives 180 WL a factor of 1.45
original BC of .513 is compromised to .505
minimum twist recommended is 9.75
it doesn't sound anything like a worrysome situation in practical real world terms, but those who obsess with number crunching model
ideals could sure invent something to worry about.... Berger does not say its wrong to hunt with a factor of 1.45,
http://www.bergerbullets.com/twist-rate-calculator/GSC bullet site indicates a stability factor of 1.4 or greater is adequate for a projectile if; 'general hunting out to 500 metres'.
considering GSC are made in Africa and used in Africa with a great reputation, I gather they know what they are talking about
in their technical advice to hunters.
It also shows a 175g Woodleigh (.510 B.C.) as “stabilized” from a 7mm RM 1-9.5 twist at 2800 fps.
Thanks, but I’ll take the 7mm RM and the "BC club" 175. Fully stabilized, flatter shooting and higher velocity and energy downrange.
how about you put your calculator down ....and in relation to the OP, just tell people what is going to 'go wrong' if a .270win owner
loads WL 180....?....How much real world effect 'worse off' are they going to be (vs) using .280AI 175 Woodleigh.....?
The “super duper BC pills and xtra long monometals” are “out of the game for most” factory rifles, regardless of chambering.
Yep.
most people use common twists with common bullet weights and get the job done at most common ranges.
Im a 7mm fan , but the hype about 280 AI and better bullet choices is exaggerated, as are some muzzle velocity claims.
ie; I doubt some are based on 'safe' loads or common length barrels.
When I asked you to show me a better deer/elk/both cartridge it was in reference to the 7mm RM, not the .280AI. ...
Hmmm.... you didn't ask me that, you asked TRYSTAN.
