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
Neck turning tool & Advice please
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="Jay Kyle" data-source="post: 343573" data-attributes="member: 347"><p><em>Bart:</em></p><p></p><p> </p><p>..and</p><p> </p><p><em>Boss:</em></p><p></p><p> </p><p> </p><p>Well, your both barking in the right direction.. </p><p> </p><p>In reality the chamber volume, case volume, and where the bullet is all change as pressure builds up during the ignition/burn sequence. Then you throw in chamber temperature and burn retardants (lube, etc) into the mix.</p><p> </p><p>The chamber expands, that's what strain gauges detect when they measure chamber pressure. The case of course expands with it. Even the bolt can deform and snap back. The bullet starts to move down the barrel at a relatively low pressure. Max pressure does not occur until the bullet is a couple of inches down the barrel.</p><p> </p><p>So this dynamic set of events are hard to predict. To model it, one has to go to an engineering firm that specializes in fluid flow computational analysis, and further, the modeling software they use MUST be able to handle a moving object in the stream, as well as changing volume - there are only a couple of very expensive packages that can do this kind of modeling. </p><p> </p><p>Well, outside of that we experiment and try different case prep processes to try and find the factor(s) that makes the most difference. It's not exact, and that leads to comments like the above. The bottom line, think through and consider ALL factors that influence the burn sequence, consider that steel DOES deform and move about, then spring back. Then prioritize and select those factors that you think will make the most difference to your shot-to-shot consistency.</p><p> </p><p> </p><p>Jay</p><p>Kyle Precision Arms</p></blockquote><p></p>
[QUOTE="Jay Kyle, post: 343573, member: 347"] [I]Bart:[/I] ..and [I]Boss:[/I] Well, your both barking in the right direction.. In reality the chamber volume, case volume, and where the bullet is all change as pressure builds up during the ignition/burn sequence. Then you throw in chamber temperature and burn retardants (lube, etc) into the mix. The chamber expands, that's what strain gauges detect when they measure chamber pressure. The case of course expands with it. Even the bolt can deform and snap back. The bullet starts to move down the barrel at a relatively low pressure. Max pressure does not occur until the bullet is a couple of inches down the barrel. So this dynamic set of events are hard to predict. To model it, one has to go to an engineering firm that specializes in fluid flow computational analysis, and further, the modeling software they use MUST be able to handle a moving object in the stream, as well as changing volume - there are only a couple of very expensive packages that can do this kind of modeling. Well, outside of that we experiment and try different case prep processes to try and find the factor(s) that makes the most difference. It's not exact, and that leads to comments like the above. The bottom line, think through and consider ALL factors that influence the burn sequence, consider that steel DOES deform and move about, then spring back. Then prioritize and select those factors that you think will make the most difference to your shot-to-shot consistency. Jay Kyle Precision Arms [/QUOTE]
Insert quotes…
Verification
Post reply
Forums
Rifles, Reloading, Optics, Equipment
Reloading
Neck turning tool & Advice please
Top