Help understanding bullet BC

[z987k]

Hang with to the point that most all of us won’t be able to detect any difference, I agree. Still, even the limited heavy for caliber bullet options in 277 are inferior on paper compared to 264 and 277 options so they are a less attractive option IMO.

Idk, the 150gr .277 SBD-2 has a G1 of .71 Even the Berger EOL 264 bullet isn't that high.

 

[bnewt3]

277 170gr EOL EH is .706 above 3000fps

 

[z987k]

Less recoil and some case efficiency/precision are gained.

You lose some wind drift with the 6cm smaller bullet.

If they have the same BC and the same velocity wind drift will be identical. Bullet diameter isn't even in the equation of wind drift. Neither is weight.

 

[Macintosh]

Bergers stability calculator says the factory 145gr precision hunter ammo is only marginally stable in my factory .270 tikka until I get up to about 5500’ elevation (I mostly hunt between 1500-3000’). If you really want to make a 270 hang with the trendy equivalents, you likely are looking at an aftermarket barrel with a faster twist to shoot the heavier bullets, handloading, and limited availability and options in components, in a addition to more recoil. I dont believe most people need or are capable of taking advantage of those advantages… but if you aspire to, all that can be had off the shelf in one of the modern 6 or 6.5’s. Makes perfect sense to me, and Im a 270 fan.

 

[wind gypsy]

277 170gr EOL EH is .706 above 3000fps

Just going off Berger’s own “quick reference sheet”, they list five 264 bullets and seven .284 bullets with a better form factor.

Idk, the 150gr .277 SBD-2 has a G1 of .71 Even the Berger EOL 264 bullet isn't that high.

Sounds looks like a slick bullet. Actually a little higher than their rated bc on 264 and 284 offerings. Are they accurate? not particularly interested in buying monos from a guy busted for child porn though..

 

[bnewt3]

According to the Berger website, a better way to compare bullets is to compare form factor or SD ÷ G7 CD as it compares to the "standard" of 1.000

In that case the 277 has a FF of .9996 or .04% better than the "standard"
The 6mm has a FF of .9674 or 3.26% better than the "standard"

I'm pretty sure I didn't screw up any of that math.

 

[ozyclint]

On a slightly different note, how would the use of material with greater density than lead, like tungsten or uranium change the BC?
Super long and skinny, high sectional density. Go down in diameter for a given bullet weight. Probably require it's own bespoke cartridge.
Ignoring terminal ballistics.
If it wasn't for availability and cost would a higher density bullet redefine long range shooting?

 

[bnewt3]

On a slightly different note, how would the use of material with greater density than lead, like tungsten or uranium change the BC?
Super long and skinny, high sectional density. Go down in diameter for a given bullet weight. Probably require it's own bespoke cartridge.
Ignoring terminal ballistics.
If it wasn't for availability and cost would a higher density bullet redefine long range shooting?

For an extreme example see

M829 - Wikipedia

en.m.wikipedia.org

It's incredible what these things do

 

[Formidilosus]

Based on what Form has said on the S2H podcast maybe a couple inches in wound channel diameter?

Between the 108gr ELD-M and 145gr ELD-X? Almost nothing. You will not be able to see it in game. Or I should say it take a massive amount of game killed with both, with good notes and proper necropsies to see the difference between an optimized 108gr bullet and an optimized 145gr bullet, and even then it will be largely irrelevant.

It’s simply this- there’s no reason other than nostalgia to take double the recoil, and 50% more powder burned to do the same thing.

 

[TaperPin]

So I was looking at bullet BCs today and I noticed that Hornady shows the exact same G1 and G7 numbers for the 6mm 108gr ELDM as the .270 143gr ELDX. Can someone explain to me why the 108 is so highly thought of and the 270 is made out to be a bowling ball?


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Shhhhh - don’t talk about a caliber from 1925 that’s been shooting 150 gr bullets from day one.

 

[z987k]

Just going off Berger’s own “quick reference sheet”, they list five 264 bullets and seven .284 bullets with a better form factor.


Sounds looks like a slick bullet. Actually a little higher than their rated bc on 264 and 284 offerings. Are they accurate? not particularly interested in buying monos from a guy busted for child porn though..

I've had them group really well for me. If you're shooting monos and you like what the Barnes do, these do it better. It's proof monos don't have to have the BC of a barn door like a lot of them do.

The child porn thing was one of his employees. Who does not work there anymore. And I'm sure is in prison. I took note of that to, but you can only do so much to screen your employees. We had a guy where I work busted for that to(also now in prison forever). You would have never guessed it. So I don't hold that against the owner.