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Rifles, Reloading, Optics, Equipment
Reloading
Reloading is so hard!
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<blockquote data-quote="bigedp51" data-source="post: 1189951" data-attributes="member: 28965"><p>We live in a plus and minus manufacturing world and chambers and dies vary in size. Example I have a standard Lee .223 die if setup per the instructions will push the shoulder back .009 shorter than my GO gauge. This same die will also reduce the case diameter smaller than my RCBS small base die. </p><p></p><p>Below a fired case from my AR15.</p><p></p><p><img src="http://i122.photobucket.com/albums/o254/bigedp51/headspacegauge005_zps20685e73.jpg" alt="" class="fr-fic fr-dii fr-draggable " style="" /></p><p></p><p>Below the same case after full length resizing and .003 shoulder bump.</p><p></p><p><img src="http://i122.photobucket.com/albums/o254/bigedp51/headspacegauge004_zps4465b7bc.jpg" alt="" class="fr-fic fr-dii fr-draggable " style="" /></p><p></p><p>Below a new unfired Federal M193 cartridge.</p><p></p><p><img src="http://i122.photobucket.com/albums/o254/bigedp51/headspacegauge002_zpscc227fb8.jpg" alt="" class="fr-fic fr-dii fr-draggable " style="" /></p><p></p><p>And below the +.004 Redding competition shell holder I used above for my .003 shoulder bump next to a standard RCBS shell holder. And if I had used the standard RCBS shell holder the case would be .002 shorter than a factory case and almost .008 shorter than my chamber.</p><p></p><p><img src="http://i122.photobucket.com/albums/o254/bigedp51/shellholders_zps0f9bb695.jpg" alt="" class="fr-fic fr-dii fr-draggable " style="" /></p><p></p><p>Bottom line, if your chamber pressure is not high enough the base of the case will not stretch to meet the bolt face. If your primer is flush with the base of the case after firing the base of the case did make contact with the bolt face. Meaning check a fired case, is the primer protruding from the base or is it flush.</p><p></p><p>The neck and shoulder of the case is the softest part of the brass and should conform to the chamber very easily. The base of the case is much harder and thicker and may take 43,000 to 45,000 psi to cause the brass to stretch to the bolt face.</p><p></p><p>If your chamber pressure is above these figures I would guess your die is a close match to your chamber.</p><p></p><p>Below is what normally happens when full length resizing and if the die is set too high you can actually make the case longer than the chamber. And if the die is set too low the will have excessive shoulder bump/shoulder setback.</p><p></p><p><img src="http://i122.photobucket.com/albums/o254/bigedp51/shouldersetback_zpsrefii5sv.jpg" alt="" class="fr-fic fr-dii fr-draggable " style="" /></p></blockquote><p></p>
[QUOTE="bigedp51, post: 1189951, member: 28965"] We live in a plus and minus manufacturing world and chambers and dies vary in size. Example I have a standard Lee .223 die if setup per the instructions will push the shoulder back .009 shorter than my GO gauge. This same die will also reduce the case diameter smaller than my RCBS small base die. Below a fired case from my AR15. [IMG]http://i122.photobucket.com/albums/o254/bigedp51/headspacegauge005_zps20685e73.jpg[/IMG] Below the same case after full length resizing and .003 shoulder bump. [IMG]http://i122.photobucket.com/albums/o254/bigedp51/headspacegauge004_zps4465b7bc.jpg[/IMG] Below a new unfired Federal M193 cartridge. [IMG]http://i122.photobucket.com/albums/o254/bigedp51/headspacegauge002_zpscc227fb8.jpg[/IMG] And below the +.004 Redding competition shell holder I used above for my .003 shoulder bump next to a standard RCBS shell holder. And if I had used the standard RCBS shell holder the case would be .002 shorter than a factory case and almost .008 shorter than my chamber. [IMG]http://i122.photobucket.com/albums/o254/bigedp51/shellholders_zps0f9bb695.jpg[/IMG] Bottom line, if your chamber pressure is not high enough the base of the case will not stretch to meet the bolt face. If your primer is flush with the base of the case after firing the base of the case did make contact with the bolt face. Meaning check a fired case, is the primer protruding from the base or is it flush. The neck and shoulder of the case is the softest part of the brass and should conform to the chamber very easily. The base of the case is much harder and thicker and may take 43,000 to 45,000 psi to cause the brass to stretch to the bolt face. If your chamber pressure is above these figures I would guess your die is a close match to your chamber. Below is what normally happens when full length resizing and if the die is set too high you can actually make the case longer than the chamber. And if the die is set too low the will have excessive shoulder bump/shoulder setback. [IMG]http://i122.photobucket.com/albums/o254/bigedp51/shouldersetback_zpsrefii5sv.jpg[/IMG] [/QUOTE]
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Reloading
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