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
Expander ball fact or fiction
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="FearNoWind" data-source="post: 1211243" data-attributes="member: 50867"><p><u>Polish the expander ball</u> </p><p>The amount of stress reduction experienced from polishing the expander ball depends on two factors. 1. How much better it is polished than it was originally 2. How much debris (carbon) is caked inside the neck to drag (friction) on the ball during expanding operations. </p><p> </p><p><u>High position expander ball</u></p><p>Full length sizing dies usually include an expander ball on the decapping rod. The models that use a "floating" expander ball are intended to be "self centering" in the case neck, and the theory is that the case neck guides the ball instead of vice versa. But if the ball self centers in the case neck and the case neck center line is not perfectly aligned with the center line of the case (and that's quite common - hence neck turning; but we'll get to that later) then all is for naught. </p><p> </p><p><u>Larger/Smaller expander ball and/or die honing</u>-</p><p>I believe what you mean here is that case neck passes over the expander ball, then it undersized as it passes in and out of the neck sizing area of the die, and is once again expanded as it makes its second pass over the expander ball. That's a common feature of full length sizing dies. It tends to "over work" the brass and that's something most reloaders would prefer to avoid. Honing the die simply means that you're removing some of the surface of its interior (usually using a steel rod of appropriate diameter, some abrasive material and a lubricant) but it requires a lot of work to do that job correctly and doing it incorrectly can produce an out of round neck sizing operation.</p><p> </p><p><u>"Cleaning up" neck thickness</u>-</p><p>OK, now let's get to neck turning. I know; it's not your favorite subject. But stay with me on this one.</p><p>You appear to have the opinion that all or nearly all of the sizing operations involve the inside of the case neck. Squeeze if down and expand it back out. All things being equal, I'd saythat's pretty much true. But when cases are manufactured their neck thickness commonly varies throughout the circumference of the neck. To make an exaggerated point - if a case neck is .005" thick on one side and .002 on the other, no amount of honing, neck expander ball polishing or other adjustment will ever produced consistent runout. The runout will always vary by .003. The only way to correct that error is to turn the case neck so that its thickness is uniform overall.</p><p>Taking it one step further, if your case neck thickness is not uniform there is no way you will ever achieve uniform neck tension.</p><p>Is it bad? - of course not. Rifles shoot very well without a lot of fuss about uniformity of neck tension/runout. But they shoot better when some attention is paid to the finer details of reloading operations.</p></blockquote><p></p>
[QUOTE="FearNoWind, post: 1211243, member: 50867"] [U]Polish the expander ball[/U] The amount of stress reduction experienced from polishing the expander ball depends on two factors. 1. How much better it is polished than it was originally 2. How much debris (carbon) is caked inside the neck to drag (friction) on the ball during expanding operations. [U]High position expander ball[/U] Full length sizing dies usually include an expander ball on the decapping rod. The models that use a "floating" expander ball are intended to be "self centering" in the case neck, and the theory is that the case neck guides the ball instead of vice versa. But if the ball self centers in the case neck and the case neck center line is not perfectly aligned with the center line of the case (and that's quite common - hence neck turning; but we'll get to that later) then all is for naught. [U]Larger/Smaller expander ball and/or die honing[/U]- I believe what you mean here is that case neck passes over the expander ball, then it undersized as it passes in and out of the neck sizing area of the die, and is once again expanded as it makes its second pass over the expander ball. That's a common feature of full length sizing dies. It tends to "over work" the brass and that's something most reloaders would prefer to avoid. Honing the die simply means that you're removing some of the surface of its interior (usually using a steel rod of appropriate diameter, some abrasive material and a lubricant) but it requires a lot of work to do that job correctly and doing it incorrectly can produce an out of round neck sizing operation. [U]"Cleaning up" neck thickness[/U]- OK, now let's get to neck turning. I know; it's not your favorite subject. But stay with me on this one. You appear to have the opinion that all or nearly all of the sizing operations involve the inside of the case neck. Squeeze if down and expand it back out. All things being equal, I'd saythat's pretty much true. But when cases are manufactured their neck thickness commonly varies throughout the circumference of the neck. To make an exaggerated point - if a case neck is .005" thick on one side and .002 on the other, no amount of honing, neck expander ball polishing or other adjustment will ever produced consistent runout. The runout will always vary by .003. The only way to correct that error is to turn the case neck so that its thickness is uniform overall. Taking it one step further, if your case neck thickness is not uniform there is no way you will ever achieve uniform neck tension. Is it bad? - of course not. Rifles shoot very well without a lot of fuss about uniformity of neck tension/runout. But they shoot better when some attention is paid to the finer details of reloading operations. [/QUOTE]
Insert quotes…
Verification
Post reply
Forums
Rifles, Reloading, Optics, Equipment
Reloading
Expander ball fact or fiction
Top