Forums
New posts
Search forums
What's new
Articles
Latest reviews
Author list
Classifieds
Log in
Register
What's new
Search
Search
Search titles and first posts only
Search titles only
By:
New posts
Search forums
Menu
Log in
Register
Install the app
Install
Forums
Hunting
Long Range Hunting & Shooting
Wind Drift
JavaScript is disabled. For a better experience, please enable JavaScript in your browser before proceeding.
You are using an out of date browser. It may not display this or other websites correctly.
You should upgrade or use an
alternative browser
.
Reply to thread
Message
<blockquote data-quote="ajhardle" data-source="post: 665926" data-attributes="member: 49861"><p>Okay, but my case is not to illistrate what can be done to a .308. I simply am trying to show that shape and velocity are very critical components of wind drift, and that higher b.c. is a great indicator, it can sometimes deceive.</p><p>I'm going to use a basic example <em><u>right from hornady's load manual</u></em>, under .308 win.</p><p>the 190 btsp with a b.c of <strong>.491</strong> and the 168 amax witha b.c. of .4<strong>75</strong>.</p><p>These are not apples to apples, i will get to that later. these just show how important shape is in the ballisitic coefficient equation. the 190 has a <strong>higher bc only because it is heavier. </strong>Hornady suggest max vel. for each is 2600 and 2400. Because the 190 is heavier, it leaves the muzzle at a lower speed.</p><p><a href="http://www.hornady.com/cgi-bin/ball10.cgi?firearm=Match&desc=168+gr+amax&wght=168&coef=.475&vel=2600&sight=1.5&temp=59&barom=29.53&zero=100&wspd=10&calcbutton=Calculate" target="_blank">Ballistics Calculator v1.0</a></p><p><a href="http://www.hornady.com/cgi-bin/ball10.cgi?firearm=Match&desc=190+btsp&wght=190&coef=.475&vel=2400&sight=1.5&temp=59&barom=29.53&zero=100&wspd=10&calcbutton=Calculate" target="_blank">Ballistics Calculator v1.0</a></p><p>as you can see, the <strong>168</strong> drifts <strong>106</strong> inches and the <strong>190</strong> drifts <strong>118. </strong>The higher bc has more drift in this scenario.</p><p>The advantage of the heavy bullet is that it will not lose velocity and eventually the 190 will have less drift. I ran the ballistics on Point Mass Ballistic Solver and the 190 has less wind drift past 2300 yards. I think 2300 yards is past this cartriges functional range, so I would use the 168.</p></blockquote><p></p>
[QUOTE="ajhardle, post: 665926, member: 49861"] Okay, but my case is not to illistrate what can be done to a .308. I simply am trying to show that shape and velocity are very critical components of wind drift, and that higher b.c. is a great indicator, it can sometimes deceive. I'm going to use a basic example [I][U]right from hornady's load manual[/U][/I], under .308 win. the 190 btsp with a b.c of [B].491[/B] and the 168 amax witha b.c. of .4[B]75[/B]. These are not apples to apples, i will get to that later. these just show how important shape is in the ballisitic coefficient equation. the 190 has a [B]higher bc only because it is heavier. [/B]Hornady suggest max vel. for each is 2600 and 2400. Because the 190 is heavier, it leaves the muzzle at a lower speed. [url=http://www.hornady.com/cgi-bin/ball10.cgi?firearm=Match&desc=168+gr+amax&wght=168&coef=.475&vel=2600&sight=1.5&temp=59&barom=29.53&zero=100&wspd=10&calcbutton=Calculate]Ballistics Calculator v1.0[/url] [url=http://www.hornady.com/cgi-bin/ball10.cgi?firearm=Match&desc=190+btsp&wght=190&coef=.475&vel=2400&sight=1.5&temp=59&barom=29.53&zero=100&wspd=10&calcbutton=Calculate]Ballistics Calculator v1.0[/url] as you can see, the [B]168[/B] drifts [B]106[/B] inches and the [B]190[/B] drifts [B]118. [/B]The higher bc has more drift in this scenario. The advantage of the heavy bullet is that it will not lose velocity and eventually the 190 will have less drift. I ran the ballistics on Point Mass Ballistic Solver and the 190 has less wind drift past 2300 yards. I think 2300 yards is past this cartriges functional range, so I would use the 168. [/QUOTE]
Insert quotes…
Verification
Post reply
Forums
Hunting
Long Range Hunting & Shooting
Wind Drift
Top