Forums
New posts
Search forums
What's new
New posts
New media
New media comments
Latest activity
Classifieds
Media
New media
New comments
Search media
Log in
Register
What's New?
Search
Search
Search titles only
By:
New posts
Search forums
Menu
Log in
Register
Navigation
Install the app
Install
More Options
Advertise with us
Contact Us
Close Menu
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
.
Forums
The Range
Ammo & Reloading
Ready to collect mo data on 6.5 creedmoor
Search titles only
By:
Reply to Thread
This site may earn a commission from merchant affiliate links, including eBay, Amazon, and others.
Message
<blockquote data-quote="dennishoddy" data-source="post: 3169506" data-attributes="member: 5412"><p>As I'm into hyper velocity calibers like .22-250 and .243 WSSM the rate of twist and velocity make all the difference in the world. I've had to build two different rifles in the .243 WSSM to attain the accuracy. 1:8 for the 80-100 grain, 1:12 for the 55 grain. </p><p>I'll steal Jcanns reference about why so I don't have to type it. </p><p></p><p>you may need somewhat MORE RPM as you increase velocity, because more speed puts more pressure, a destabilizing force, on the nose of the bullet. You need to compensate for that destabilizing force with somewhat more RPM. But, as a general rule, if you increase velocity you CAN decrease twist rate. What’s the benefit? The slower twist-rate barrel may, potentially, be more accurate. And barrel heat and friction may be reduced somewhat.</p><p></p><p>Just remember that as you reduce twist rate you need to increase velocity, and you may need somewhat MORE RPM than before. (As velocities climb, destabilizing forces increase somewhat, RPM being equal.)</p></blockquote><p></p>
[QUOTE="dennishoddy, post: 3169506, member: 5412"] As I'm into hyper velocity calibers like .22-250 and .243 WSSM the rate of twist and velocity make all the difference in the world. I've had to build two different rifles in the .243 WSSM to attain the accuracy. 1:8 for the 80-100 grain, 1:12 for the 55 grain. I'll steal Jcanns reference about why so I don't have to type it. you may need somewhat MORE RPM as you increase velocity, because more speed puts more pressure, a destabilizing force, on the nose of the bullet. You need to compensate for that destabilizing force with somewhat more RPM. But, as a general rule, if you increase velocity you CAN decrease twist rate. What’s the benefit? The slower twist-rate barrel may, potentially, be more accurate. And barrel heat and friction may be reduced somewhat. Just remember that as you reduce twist rate you need to increase velocity, and you may need somewhat MORE RPM than before. (As velocities climb, destabilizing forces increase somewhat, RPM being equal.) [/QUOTE]
Insert Quotes…
Verification
Post Reply
Forums
The Range
Ammo & Reloading
Ready to collect mo data on 6.5 creedmoor
Search titles only
By:
Top
Bottom
