The Firing Line Forums

Go Back   The Firing Line Forums > The Skunkworks > Handloading, Reloading, and Bullet Casting

Reply
 
Thread Tools Search this Thread
Old March 2, 2012, 09:01 PM   #1
ScottRiqui
Senior Member
 
Join Date: January 27, 2010
Location: Norfolk, VA
Posts: 2,905
Using Dillon Case Gauge?

I just received my Dillon rifle case gauge for .223. Here's what it looks like:



Just to make sure I understand correctly, if a fired case drops freely into the gauge, and both the head and mouth ends fall between the high and low surfaces, then I don't need to full-length size or trim the case? I can just neck-size it and proceed from there with repriming/charging/seating?

The ammo will be used in an AR for "blasting/plinking".
ScottRiqui is offline  
Old March 2, 2012, 09:16 PM   #2
Slamfire
Senior Member
 
Join Date: May 27, 2007
Posts: 5,261
If you fired case drops in between the Go and No Go all that indicates is that your chamber headspace is correct.

These case gages are cut large between shoulder and base so you can drop in fired cases and determine an approximate chamber headspace.

These gages measure length, they do not measure "fatness".

I am confident that your once fired brass will be an interference fit in the chamber of your AR15.

I am also confident that once you size your brass, it will need trimming. My once fired brass always grows beyond max trim length on its first sizing.

Full length size your cases and use the cartridge headspace gage to set up your sizing die. Size the case about 0.003" less than the fired case.

__________________
If I'm not shooting, I'm reloading.
Slamfire is offline  
Old March 2, 2012, 09:26 PM   #3
jepp2
Senior Member
 
Join Date: December 24, 2008
Location: Loveland, CO
Posts: 1,476
Quote:
Just to make sure I understand correctly, if a fired case drops freely into the gauge, and both the head and mouth ends fall between the high and low surfaces, then I don't need to full-length size or trim the case?
Slamfire's photo shows very well the use of the gage. For semiautos, you should always full length size. Always. You can use your Dillon gage to set your die properly for your rifle's headspace. And after sizing you can use it to check if the brass needs to be trimmed.

At least in my Wilson gage any type of burr on the rim of the case will prevent it from allowing the gage to work properly. So just make sure you realize the limitation of the gage. I find a caliper to be much more useful in setting up my trimmer. YMMV.
jepp2 is offline  
Old March 2, 2012, 10:49 PM   #4
ScottRiqui
Senior Member
 
Join Date: January 27, 2010
Location: Norfolk, VA
Posts: 2,905
Thanks for the replies - knowing that the case gauge is only for measuring *length* between reference points on the case and not the *diameter* of the case helps a lot. I was under the (mistaken) impression that it would also serve the same function as dropping a case into a gun's chamber.

I'll continue to full-length size all of my cases, especially since most of my once-fired brass wasn't fired in *my* AR in the first place.
ScottRiqui is offline  
Old February 3, 2014, 09:08 AM   #5
Bwell
Junior Member
 
Join Date: December 30, 2013
Posts: 11
What if your brass is flush with the low step?
Bwell is offline  
Old February 3, 2014, 09:20 AM   #6
SWThomas
Member
 
Join Date: August 17, 2013
Location: Fort Lee, VA
Posts: 73
I got one of those gauges and quickly relegated it to paper weight duty. They're pretty worthless. I comparator body and a bump gauge for it is all I use now. Yes, a fired case will sometimes look perfect in a case gauge, but the shoulder still needs a bump and the neck still needs to be sized back down. Hence the worthlessness of the case gauge. They're good for pistol rounds.
SWThomas is offline  
Old February 3, 2014, 10:11 AM   #7
higgite
Senior Member
 
Join Date: October 21, 2010
Posts: 1,024
As jepp2 said, for blasting/plinking ammo for an AR, you do need to full length size your brass, regardless of what the gauge shows before resizing. Otherwise, you're asking for auto feed problems. Use the gauge to set your FL sizing die to size the shoulder-head length such that the head falls between the steps in the gauge. Then use the length checking feature of the gauge to check if the neck needs trimming.

If you didn't get instructions with the gauge, check out page 7 of this link from Dillon's website.
http://www.dillonprecision.com/docs/...l_may_2007.pdf

IMHO, you only need more precise measuring tools, such as comparators and such, if you're going to make more precise ammo. For blasting/plinking AR ammo, the Dillon gauge is enough if used as it's designed to be used.
higgite is offline  
Old February 3, 2014, 10:50 AM   #8
F. Guffey
Senior Member
 
Join Date: July 18, 2008
Posts: 7,249
I got one of those gauges and quickly relegated it to paper weight duty. They're pretty worthless. I comparator body and a bump gauge for it is all I use now. Yes, a fired case will sometimes look perfect in a case gauge, but the shoulder still needs a bump and the neck still needs to be sized back down. Hence the worthlessness of the case gauge. They're good for pistol rounds.

“I comparator “ I will assume ‘use a’ was omitted.

The sequence of events? Fire then measure, then size and compare. L.E. Wilson makes it very clear the case gage is not a chamber gage. They also give options, back when pocket rules were common they suggested using ‘a pocket rule’ across the top of the die, if the case protruded they suggested using the pocket rule across the case head, to check for daylight. I have never thought about measuring the width of light so I used a feeler gage.

I measure the length of the case from the datum to the case head with a feeler gage. One step on the case gage is minimum length, the other height is go-gage length. If the gage is not correct, I can verify with a straight edge and a feeler gage, I can also verify the Case gage with a go-gage, or a no go-gage, and a field reject gage. Any reloader that has the ability to measure the length of a case from the datum/shoulder to the head of the case can verify the accuracy of a case gage.

Put another way, a reloader that has the ability to measure the length of a case from the shoulder to the head of the case does not need a case gage. then there is the paper weight.

The paper weight can measure the length of the case from the datum to the end of the neck, it also measures the length of the case from the datum to the head of the case. Any reloader can verify the accuracy of a case gage by measuring the distance from the bottom cut to the neck end of the gage to get case length, the 30/06 case gage measures 2.494.

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

Slam fire has custom chamber gages, I make chamber gages. I do not give it a second thought, when I need a chamber gage I cut a chamber from a barrel. I purchased 4 receivers with shot out barrels for $25.00 each, I cut the chambers off and used them as chamber gages. With a difference, I matched the case head protrusion from the gage with the chamber in the rifle. I know, that is confusing. A friend came over from the range. He had a box of 30/06 new in a box just fired in a new Ruger rifle, problem, 5 did not fire. I dug out a pile of tools that included the chamber gages. All of the 20 cases chambered in the chamber gage, We determined the length of the rifles chamber with the gage, we verified the length with a Wilson case gage, we again verified the length of the cases that were fired and the ones that did not fire, we were impressed. We pulled the unfired cases down and measured the components, again,most impressive. impressive, we removed the primers. The primers had been struck 5 timesa with 3 different rifles.

We then installed the primers back into the cases they were removed from, one at a time I chambered the cases without bullet or powder, in one of my M1917s and fired all 5 primers. When ejected the primers did not protrude from the case head and the firing pin striking the primer did not shorten the case body from the shoulder to the case head. I was very impressed with the primers, they had been hammered 5 times, removed and then reinstalled and after all of that abuse, they worked.

My friend called me about 4 hours after returning home, he wanted to know where he could find the tools we used, he wanted to know the manufacturer and name of the tools.

F. Guffey
F. Guffey is offline  
Old February 3, 2014, 10:58 AM   #9
F. Guffey
Senior Member
 
Join Date: July 18, 2008
Posts: 7,249
and then then I asked him for information about the shooter that was not happy with his new Remington ammo in his new Ruger rifle, nothing. I ask if they called Remington, nothing.

I concluded all 20 rounds would have fired in one of my M1917s, the M1917 has a killer firing pin, most rifles make the click sound, my M 1917 make that CLICK!!! sound.

F. Guffey
F. Guffey is offline  
Old February 3, 2014, 11:11 AM   #10
F. Guffey
Senior Member
 
Join Date: July 18, 2008
Posts: 7,249
Quote:
Just to make sure I understand correctly, if a fired case drops freely into the gauge, and both the head and mouth ends fall between the high and low surfaces, then I don't need to full-length size or trim the case?
"understand correctly?"

If I wrote the instructions you would have 'dropped' the case into the gage before you fired it. THEN! you would know 'what will chamber' before you sized the case then found there is something wrong, like your sized case will not chamber. the instructions are clear, I have a set that goes back to 1955.

There are two three length measurements, it is possible to have a case that protrudes from the top of the case gage, it is possible to have a case that is too long form the head of the case to the end of the neck that does not require trimming except for those that are conditioned to trim.

there is in front of the datum, there is behind the datum.

F. Guffey

Last edited by F. Guffey; February 3, 2014 at 11:21 AM. Reason: change goers to goes
F. Guffey is offline  
Old February 3, 2014, 11:20 AM   #11
F. Guffey
Senior Member
 
Join Date: July 18, 2008
Posts: 7,249
The straight edge/steel pocket rule is not absolutely necessary. there is the set-up/lay-out table or flat surface, when measuring case head protrusion.

stand the case up on a flat surface then place the case gage on the case, then with a feeler gage measure the gap between the flat surface and the head of the gage.

Remember, a case that protrudes is longer than a go gage.

How much? Add the thickness of the feeler gage to the length of the go-gage when measured from the datum to the head of the go-gage.

F. Guffey

Last edited by F. Guffey; February 3, 2014 at 11:22 AM. Reason: change of to or
F. Guffey is offline  
Reply

Thread Tools Search this Thread
Search this Thread:

Advanced Search

Posting Rules
You may not post new threads
You may not post replies
You may not post attachments
You may not edit your posts

BB code is On
Smilies are On
[IMG] code is On
HTML code is Off

Forum Jump


All times are GMT -5. The time now is 04:41 PM.


Powered by vBulletin® Version 3.8.7
Copyright ©2000 - 2024, vBulletin Solutions, Inc.
This site and contents, including all posts, Copyright © 1998-2021 S.W.A.T. Magazine
Copyright Complaints: Please direct DMCA Takedown Notices to the registered agent: thefiringline.com
Page generated in 0.08151 seconds with 8 queries