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
Setting dies for a belted mag?
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="woods" data-source="post: 470185" data-attributes="member: 6042"><p>Maybe the guy is just looking for a simple explanation, if so:</p><p></p><p>1. Set your gun up on the bench and close the bolt paying attention to the amount of force needed on the bolt handle to close it</p><p>2. Take a fired case and chamber it and see if it takes more force to close the bolt, it will be only a slight difference most times but you can feel the case being tight in the chamber, called a "crush fit"</p><p>3. If you do not have a crush fit then you need to size without pushing the shoulder back. You can size the case body but need to let the case shoulder continue to move forward with subsequent firings until you get the crush fit. Depending upon exactly where your case shoulder is, sizing the case body will squeeze the case like a balloon and push the shoulder forward so you need to try the case again after sizing. To set your die to size the case body and the neck without touching the shoulder, thread it in until it hits the raised shell holder and then BACK IT UP about 1/4 turn. That will size ~90% of the neck and almost all the case body. Again check the case in your chamber to see if it has ballooned forward to a crush fit.</p><p>4. If you do have a crush fit then you need to size to push the shoulder back the least amount possible to get rid of or greatly alleviate the crush fit. To do this with a normal FL die, thread the die in until it hits the raised shell holder and size a case. Try it in your chamber. The crush fit may still be there or may have gotten worse (that ballooning thing again). THREAD THE DIE IN a very small amount and try the case in your chamber again. Keep doing this until you feel the crush fit go away or decrease, IOW when the bolt closes easier. This usually happens when you have threaded the die IN OR DOWN an additional 1/8 turn from where it hit the shell holder. It helps if you put witness marks on the die and press</p><p><img src="http://img.photobucket.com/albums/v663/bwestfall/RELOADING/DSCN0140.jpg" alt="" class="fr-fic fr-dii fr-draggable " style="" /></p><p></p><p></p><p>It helps if you have a headspace gauge. I use the Hornady headspace gauge and it attaches to your caliper and takes a measurement on the shoulder</p><p></p><p><img src="http://img.photobucket.com/albums/v663/bwestfall/RELOADING/DSCN0058.jpg" alt="" class="fr-fic fr-dii fr-draggable " style="" /></p><p></p><p><img src="http://img.photobucket.com/albums/v663/bwestfall/CASE%20PREP/DSCN0557.jpg" alt="" class="fr-fic fr-dii fr-draggable " style="" /></p><p></p><p>That way you can track exactly how much your case is expanding and use the gauge to keep from pushing the shoulder back too far (.001" to .002" good .003"+ too far).</p><p></p><p>Here is an example of the belted magnum problem being discussed and how it can be a hidden problem that will not show up with the gunsmith go-no-go headspace gauges. 264 win mag Model 70</p><p></p><p><img src="http://img.photobucket.com/albums/v663/bwestfall/RELOADING/DSCN1696.jpg" alt="" class="fr-fic fr-dii fr-draggable " style="" /></p><p></p><p><img src="http://img.photobucket.com/albums/v663/bwestfall/RELOADING/DSCN1697.jpg" alt="" class="fr-fic fr-dii fr-draggable " style="" /></p><p></p><p>that is an expansion of close to .040" on new cases even though the actual headspace as measured on the belt was only .007". That excessive expansion is what leads to case head separations.</p><p></p><p>Hopefully this helps but if you already knew all this then I have just bored us all to tears and disregard as necessary.</p></blockquote><p></p>
[QUOTE="woods, post: 470185, member: 6042"] Maybe the guy is just looking for a simple explanation, if so: 1. Set your gun up on the bench and close the bolt paying attention to the amount of force needed on the bolt handle to close it 2. Take a fired case and chamber it and see if it takes more force to close the bolt, it will be only a slight difference most times but you can feel the case being tight in the chamber, called a "crush fit" 3. If you do not have a crush fit then you need to size without pushing the shoulder back. You can size the case body but need to let the case shoulder continue to move forward with subsequent firings until you get the crush fit. Depending upon exactly where your case shoulder is, sizing the case body will squeeze the case like a balloon and push the shoulder forward so you need to try the case again after sizing. To set your die to size the case body and the neck without touching the shoulder, thread it in until it hits the raised shell holder and then BACK IT UP about 1/4 turn. That will size ~90% of the neck and almost all the case body. Again check the case in your chamber to see if it has ballooned forward to a crush fit. 4. If you do have a crush fit then you need to size to push the shoulder back the least amount possible to get rid of or greatly alleviate the crush fit. To do this with a normal FL die, thread the die in until it hits the raised shell holder and size a case. Try it in your chamber. The crush fit may still be there or may have gotten worse (that ballooning thing again). THREAD THE DIE IN a very small amount and try the case in your chamber again. Keep doing this until you feel the crush fit go away or decrease, IOW when the bolt closes easier. This usually happens when you have threaded the die IN OR DOWN an additional 1/8 turn from where it hit the shell holder. It helps if you put witness marks on the die and press [IMG]http://img.photobucket.com/albums/v663/bwestfall/RELOADING/DSCN0140.jpg[/IMG] It helps if you have a headspace gauge. I use the Hornady headspace gauge and it attaches to your caliper and takes a measurement on the shoulder [IMG]http://img.photobucket.com/albums/v663/bwestfall/RELOADING/DSCN0058.jpg[/IMG] [IMG]http://img.photobucket.com/albums/v663/bwestfall/CASE%20PREP/DSCN0557.jpg[/IMG] That way you can track exactly how much your case is expanding and use the gauge to keep from pushing the shoulder back too far (.001" to .002" good .003"+ too far). Here is an example of the belted magnum problem being discussed and how it can be a hidden problem that will not show up with the gunsmith go-no-go headspace gauges. 264 win mag Model 70 [IMG]http://img.photobucket.com/albums/v663/bwestfall/RELOADING/DSCN1696.jpg[/IMG] [IMG]http://img.photobucket.com/albums/v663/bwestfall/RELOADING/DSCN1697.jpg[/IMG] that is an expansion of close to .040" on new cases even though the actual headspace as measured on the belt was only .007". That excessive expansion is what leads to case head separations. Hopefully this helps but if you already knew all this then I have just bored us all to tears and disregard as necessary. [/QUOTE]
Insert quotes…
Verification
Post reply
Forums
Rifles, Reloading, Optics, Equipment
Reloading
Setting dies for a belted mag?
Top