How much should your neck expand when fired? Is there a proper amount
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Re: neck question
<div class="ubbcode-block"><div class="ubbcode-header">Originally Posted By: aloreman</div><div class="ubbcode-body">How much should your neck expand when fired? Is there a proper amount </div></div>
Fired cases/necks generally expand to fill up the chamber, then spring back a bit.
Factory barrels generally tend to blow out the necks more than match barrels with tight chambers (troats/leades in this case).
My Savage 10FP blows out my fired necks to .343"-.345".
My AR-15 Bushy upper blows out my necks to .254"-.255".
For reference.
Chris
<div class="ubbcode-block"><div class="ubbcode-header">Originally Posted By: aloreman</div><div class="ubbcode-body">How much should your neck expand when fired? Is there a proper amount </div></div>
Fired cases/necks generally expand to fill up the chamber, then spring back a bit.
Factory barrels generally tend to blow out the necks more than match barrels with tight chambers (troats/leades in this case).
My Savage 10FP blows out my fired necks to .343"-.345".
My AR-15 Bushy upper blows out my necks to .254"-.255".
For reference.
Chris
Re: neck question
Yes this i understand. I have a tite chamber in my 338 lapua. It is also a wee bit on the short side. my loaded ammo is .368 and my fired ammo is .3715. every once in a while im getting a case stuck in the gun and was wondering if the neck may be to tight requiring a little bit to be turned off the necks
Yes this i understand. I have a tite chamber in my 338 lapua. It is also a wee bit on the short side. my loaded ammo is .368 and my fired ammo is .3715. every once in a while im getting a case stuck in the gun and was wondering if the neck may be to tight requiring a little bit to be turned off the necks
Re: neck question
Knowledgeable folks recommend more neck clearance with larger calibers and magnum cartridges. There are plenty of match-grade 308WINs with .006 of clearance between the loaded round neck diameter and the chamber dimension. I'd use .006 of clearance as a safe number and little bit more probably would not hurt anything. That is a little more than your numbers, but I doubt that is why you are getting sticky cases. Lower your charge and/or inspect your case dimensions before and after resizing: you may not be sizing the cases enough. I assume you are full-length resizing?
Knowledgeable folks recommend more neck clearance with larger calibers and magnum cartridges. There are plenty of match-grade 308WINs with .006 of clearance between the loaded round neck diameter and the chamber dimension. I'd use .006 of clearance as a safe number and little bit more probably would not hurt anything. That is a little more than your numbers, but I doubt that is why you are getting sticky cases. Lower your charge and/or inspect your case dimensions before and after resizing: you may not be sizing the cases enough. I assume you are full-length resizing?
Re: neck question
The charge is not the issue as i had stuck cases at 83 grains and up of h1000. I am using a redding body die to bump the shoulders back .002 and then a type s neck die
The charge is not the issue as i had stuck cases at 83 grains and up of h1000. I am using a redding body die to bump the shoulders back .002 and then a type s neck die
Re: neck question
Benchrest guns with fitted necks run 0.001-0.0015 throat bigger than neck kinds of tollerances.
Tight long range chambers run 0.005-0.006 (PALMA 95)
Typical factory chambers run 0.008-0.012
The benchrest chamber can be reloaded and fired without even bothering to size the brass, but have no tollerance for even the smallest partilcles of dirt and grime.
So, somewhere between tight long range chambers and typical factory chambers will be loose enough to put up with less than sparkling ammo and function just fine. Large enough that the case needs to be sized, not so tight that the case is worn out in just a few firings.
Benchrest guns with fitted necks run 0.001-0.0015 throat bigger than neck kinds of tollerances.
Tight long range chambers run 0.005-0.006 (PALMA 95)
Typical factory chambers run 0.008-0.012
The benchrest chamber can be reloaded and fired without even bothering to size the brass, but have no tollerance for even the smallest partilcles of dirt and grime.
So, somewhere between tight long range chambers and typical factory chambers will be loose enough to put up with less than sparkling ammo and function just fine. Large enough that the case needs to be sized, not so tight that the case is worn out in just a few firings.
Re: neck question
thank you
thank you
