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
Better accuracy with Virgin Brass?
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="bigedp51" data-source="post: 1180571" data-attributes="member: 28965"><p>I collected milsurp rifles with long fat chamber that tortured thinner commercial brass. I had your same problem magnified and got very good groups with new brass but the same case reloaded would shoot shotgun patterns.</p><p></p><p>The problem was the large diameter military chambers and cases with unequal case wall thicknesses. This caused the cases to warp excessively and become banana shaped when fired, this warping causes the base of the case to tilt and no longer be 90 degrees to the axis of the bore. Meaning if you set the case on its base it looks like the "Leaning Tower of Pisa".</p><p></p><p>The case will expand more on the thin side of the case and the spring back action of the brass causes the case to warp. When you full length resize the case it causes the case to tilt even more at the base increasing the warping. The smaller the diameter of the new case in relation to the diameter of the chamber increases the warping effect.</p><p></p><p>You may have a bad batch of brass with unequal case wall thickness, a off center chamber, defective dies, a expander pulling the necks off center or all of the above.</p><p></p><p>You will need a good gauge to find and check for these problems.</p><p></p><p><img src="http://i122.photobucket.com/albums/o254/bigedp51/runout_zpsfe87d011.jpg" alt="" class="fr-fic fr-dii fr-draggable " style="" /></p><p></p><p>If you really want to truly experience warped banana shaped cases then just collect British Enfield rifles and shoot Winchester brass. Now think about what is happening in front of the belt when the cartridge is fired.</p><p></p><p> <img src="http://i122.photobucket.com/albums/o254/bigedp51/headspacestretch-c_zps8f362fcb.gif" alt="" class="fr-fic fr-dii fr-draggable " style="" /></p></blockquote><p></p>
[QUOTE="bigedp51, post: 1180571, member: 28965"] I collected milsurp rifles with long fat chamber that tortured thinner commercial brass. I had your same problem magnified and got very good groups with new brass but the same case reloaded would shoot shotgun patterns. The problem was the large diameter military chambers and cases with unequal case wall thicknesses. This caused the cases to warp excessively and become banana shaped when fired, this warping causes the base of the case to tilt and no longer be 90 degrees to the axis of the bore. Meaning if you set the case on its base it looks like the "Leaning Tower of Pisa". The case will expand more on the thin side of the case and the spring back action of the brass causes the case to warp. When you full length resize the case it causes the case to tilt even more at the base increasing the warping. The smaller the diameter of the new case in relation to the diameter of the chamber increases the warping effect. You may have a bad batch of brass with unequal case wall thickness, a off center chamber, defective dies, a expander pulling the necks off center or all of the above. You will need a good gauge to find and check for these problems. [IMG]http://i122.photobucket.com/albums/o254/bigedp51/runout_zpsfe87d011.jpg[/IMG] If you really want to truly experience warped banana shaped cases then just collect British Enfield rifles and shoot Winchester brass. Now think about what is happening in front of the belt when the cartridge is fired. [IMG]http://i122.photobucket.com/albums/o254/bigedp51/headspacestretch-c_zps8f362fcb.gif[/IMG] [/QUOTE]
Insert quotes…
Verification
Post reply
Forums
Rifles, Reloading, Optics, Equipment
Reloading
Better accuracy with Virgin Brass?
Top