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
Rifles, Reloading, Optics, Equipment
Reloading
Am I about to blow my face off?
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="sfdoc2000" data-source="post: 2121534" data-attributes="member: 76742"><p>Here is Chris Long's original paper on OBT nodes. <a href="http://www.the-long-family.com/OBT_paper.htm" target="_blank">http://www.the-long-family.com/OBT_paper.htm</a></p><p>Kind of a tough read unless you have a degree in engineering. But it makes sense and can help explain a lot about where shots are going on paper. </p><p>I started looking at this several years ago when I first got Quickloads and found that to hit these nodes on the first load test sometimes just doesn't work, and sometimes the nodes do not correspond with what I was seeing at the range with ladder testing. There are so many variables with the weapon, chamber volumes, brass, neck tension, that all these things cannot be fully accounted for in a simulation such as Quickloads. But simulations are just that, and unfortunately garbage in, garbage out. What I am seeing is that the predicted nodes are usually close but not right on to where I get the best groupings. There are also some intermediate nodes (between the predicted numbered nodes) that can also give tight groups. There are several threads on this subject on this site that discuss this. </p><p>Quickloads can help reduce your time in load development by comparing initial load results with range results, and modification of your loads using this information over three or four iterations. Once you get a good load then you can experiment with neck tensions, seating depths, although some like to go with seating depth first then determine optimal powder charge and resultant muzzle velocity. Do what works best for you and carefully examine your brass for overpressure signs.</p></blockquote><p></p>
[QUOTE="sfdoc2000, post: 2121534, member: 76742"] Here is Chris Long's original paper on OBT nodes. [URL]http://www.the-long-family.com/OBT_paper.htm[/URL] Kind of a tough read unless you have a degree in engineering. But it makes sense and can help explain a lot about where shots are going on paper. I started looking at this several years ago when I first got Quickloads and found that to hit these nodes on the first load test sometimes just doesn't work, and sometimes the nodes do not correspond with what I was seeing at the range with ladder testing. There are so many variables with the weapon, chamber volumes, brass, neck tension, that all these things cannot be fully accounted for in a simulation such as Quickloads. But simulations are just that, and unfortunately garbage in, garbage out. What I am seeing is that the predicted nodes are usually close but not right on to where I get the best groupings. There are also some intermediate nodes (between the predicted numbered nodes) that can also give tight groups. There are several threads on this subject on this site that discuss this. Quickloads can help reduce your time in load development by comparing initial load results with range results, and modification of your loads using this information over three or four iterations. Once you get a good load then you can experiment with neck tensions, seating depths, although some like to go with seating depth first then determine optimal powder charge and resultant muzzle velocity. Do what works best for you and carefully examine your brass for overpressure signs. [/QUOTE]
Insert quotes…
Verification
Post reply
Forums
Rifles, Reloading, Optics, Equipment
Reloading
Am I about to blow my face off?
Top