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Bart B. · April 2, 2014, 07:22 AM

riverratt, Here's some pictures of how to use a 30 cent nylon spacer with a digital caliper to measure your fired cases then after sizing them to see how much their shoulder gets set back. Meanwhile, if there's an Ace Hardware store nearby, stop by it then buy a 1/2 inch long nylon spacer with a 3/8ths inch inside diameter. Then buy or borrow a digital caliper; a "must have" tool for reloaders in my opinion.

You'll also want to use these labels on your die so you can change its height in the press very precise to control how much sizing the cases get.

http://i860.photobucket.com/albums/a...justment-1.jpg

Note the last picture shows the case to have its shoulder set back .001 inch so it measures 2.047 inch. Perfect for best accuracy, feeding reliably and long case life.

Here's some drawings of the case and chamber that may help you see where the measurements I got came from. Note the "headspace" dimension for the chamber drawing:

http://www.saami.org/PubResources/CC...pringfield.pdf

Note also that the diameter of the reference point on both the chamber shoulder and case shoulder is .375 inch; same diameter as the hole in that nylon spacer. And after you full length size several cases, there'll be a small spread (few thousandths) across their headspace measurements. You may need to reset the die so the longest one is no longer than that of the fired case.

April 2, 2014, 07:22 AM	#35
Bart B. Senior Member Join Date: February 15, 2009 Posts: 8,927	riverratt, Here's some pictures of how to use a 30 cent nylon spacer with a digital caliper to measure your fired cases then after sizing them to see how much their shoulder gets set back. Meanwhile, if there's an Ace Hardware store nearby, stop by it then buy a 1/2 inch long nylon spacer with a 3/8ths inch inside diameter. Then buy or borrow a digital caliper; a "must have" tool for reloaders in my opinion. You'll also want to use these labels on your die so you can change its height in the press very precise to control how much sizing the cases get. http://i860.photobucket.com/albums/a...justment-1.jpg Note the last picture shows the case to have its shoulder set back .001 inch so it measures 2.047 inch. Perfect for best accuracy, feeding reliably and long case life. Here's some drawings of the case and chamber that may help you see where the measurements I got came from. Note the "headspace" dimension for the chamber drawing: http://www.saami.org/PubResources/CC...pringfield.pdf Note also that the diameter of the reference point on both the chamber shoulder and case shoulder is .375 inch; same diameter as the hole in that nylon spacer. And after you full length size several cases, there'll be a small spread (few thousandths) across their headspace measurements. You may need to reset the die so the longest one is no longer than that of the fired case. Last edited by Bart B.; April 2, 2014 at 11:19 AM.