223 Case Gauge

Bucksnort1

New member
I have a Lyman 223 case gauge. After resizing, I check each case in the gauge. The case will drop but not completely. Each case protrudes above the gauge about the thickness of the rim, sometimes less. I checked some Winchester factory ammunition, which does the same thing.

I don't think this is a problem because my reloads chamber well in a bolt action 223 but, I'm just curious about this.
 
Does it protrude past the very end of the gauge or just past the recessed channel on the end of the gauge? Got a pic of it?
 
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"...my reloads chamber well..." That's all that matters. The chamber is the very best gauge. Rule Number One. It works. Don't fix it.
Mind you, bolt actions are more forgiving than any other action. The camming action is far stronger than other types.
However, if the sizer die(assuming it's an FL die) isn't set up right, it's not sizing the whole case.
 
Bucksnort1,

If it were just your resized cases doing this, I would suggest the extractor on your gun is bending and/or burring the rim a little. But if brand new, never-fired Winchester cases won't drop in. that's a pretty good sign the gauge has a problem the factory should look at.
 
Same as any chamber gage, it is something used to set up your sizing die when you don't know what gun the cases may have to feed in. Good for owners of several guns chambered for the same cartridge. Otherwise, as mentioned, your gun's chamber is the best gauge. It can, however, be a bit inconvenient to manipulate the rifle at the loading bench, so a number of fellows take barrel blank ends or sometimes the chamber end of an old barrel cut back and finish chambered with the same reamer they used to cut the chamber in their rifle. This is a customized gage for the same gun, and the high step is made at the actual headspace of the chamber.
 
Are you full or neck sizing your brass ?
What type of action , make and model ?
Im using the Lyman case gauge for pistol 45acp , have one for 308 but haven't used it in awhile .
Would like to know how your sizing your brass first .
 
I use the same case gauge. After full-length sizing, my cases will drop right in and I can check for length. Once fired cases from my rifle, after neck-sizing only, will not fit in the case gauge; however, they will chamber fine in my rifle.
 
If you followed the post, new factory ammo won't fit, so it's not his resizing method. Really seems like the gage isn't made correctly.
 
The gun is a Savage .223 bolt action.

I full length resize with RCBS die.

T. O'Heir, I agree. If they chamber ok then all is ok.

Higgite, it protrudes slightly into the machined channel.

I will contact Lyman to see what they want me to do.
 
Buck, if it protrudes slightly into the machined groove but still below the flat end of the gauge, that's right in the good to go zone. If the flat base of the case is between flush with the bottom of the groove and flush with the top of the groove, it should fit any standard SAAMI 223 Rem chamber. If you can drag a straight edge across the end of the gauge without snagging the case, the case is not too long.
 
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higgite,

I cannot drag a straight edge across the gauge without snagging the head. I also checked some PMC cartridges. They are similar to the Winchester in that you cannot snag the case head. I will test some sized cases without powder or bullets in my rifle. I just don't recall having problems with any of my reloads not chambering.
 
If the store bought rounds are doing the same thing , I for some reason went over that part . Agree there's something wrong with the gage . Must have been made on a Monday. Let us know how it goes with the new gage . Look into the RCBS Precision Mic great tool to check headspace an ogive measurements .
 
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Case gauges are minimal SAAMI dimensions and only "tight" or undersize ammo will really fit.

FWIW; I gave up on case gauges long ago; one time I chased my tail for a month trying to find why my 30-06 Garand reloads wouldn't fit my gauge. I tried die adjustments, double checked case length, burrs, dings or bulges. The case looked good with a close visual inspection. I also tried new dies, RCBS, and same result, about .010"-,015" above the max step on the gauge. I asked around and an old Garand shooter/reloader asked "do they chamber?". They did, and shot well. Later upon examination, (further searching for why) I discovered the case was hitting the OP rod on it's way out and dinging the rim .010". I had similar problems with my semi-autos and shelved the gauge and just plunk test my ammo...
 
The gauge should not be tighter in diameter than SAAMI standard minimum chamber numbers. The whole point of those standards is cross-compatibility of ammunition with chambers made for it. Fired .223 and 5.56 cases not fitting would be no surprise, as there are now a number of .223 chamber designs (NATO and Wylde, for example) that are wider at the back end than the SAAMI standard chamber. This is mainly in order to have extra-good feed reliability, but that increased reliability only happens if the cartridge cases being fed into those chambers are within the standard case diameters. Neither Winchester nor any other new ammunition manufacturer will be making extra wide ammunition for them, as that defeats the purpose of the chamber's extra width and spoils compatibility with standard chambers into the bargain. So that new commercial cartridge not fitting into the gauge was the coroner's verdict on it for me. Something is wrong with the gauge or is stuck down inside it.

I hope the OP will let us know if the factory tells him what it was, but they will probably just do what he said, and send another.
 
I recently purchased a Sheridan slotted case gauge in 223 and 308. In addition to the length and width measures at the ends, I can also see how the case mouth and bullet fits into the throat. Of course loaded ammo fits perfectly. Now, if only my guns all had that same chamber! I know one does, and one will take longer.
 
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The case gage: The case gage has been with us from 1938 +/- a few years. I would thin it would be a rather simple gage. For me it does not get easier to use because it started out as a datum based tool. I have a choice, purchase datum based tools or make my own datums.

When I make a datum I start with zero, when I use the case gage I have another choice; I can verify the case gage or measure the length of the case from my datum to the case head to get the case length from the datum/shoulder to the case head. Most reloaders have case head space.

In the beginning reloaders thought the case gage was a drop-on gage; they did not measure before and again after, they did not consider the accuracy of the case gage and they failed to take the instructions seriously. From the beginning Wilson suggested the reloader use a straight edge; that was back when most reloaders had shop skills and carried a metal pocket rule. Wilson suggested using the pocket rule as a straight edge. For me it was a simple short step to go from a straight to adding a feeler.


I would suggest the reloader measure the length of the case form from the datum/shoulder to the case head before firing and again after firing.

F. Guffey
 
The gauge should not be tighter in diameter than SAAMI standard minimum chamber numbers.

Again; the case gage measures the length of the case from the datum/shoulder to the case head before firing and is used to measure the same case after firing.

There is another length to be measured but reloaders are so infatuated with the case having head space they forget the case gage is also used to measure the distance from the datum forward to the end of the neck. That information is helpful when determining case stretch, well... it helps me but my cases do not have case head space and I have no trouble determining what happens to the shoulder when the case is fired and or sized.

F. Guffey
 
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That's a good point. If the diameter of your gauge permits it, drop a fired case in to see where the neck and rim land, knowing that fits in your chamber and not just what SAAMI standards want it to be. Resize the case and check the neck position again to see how much it grew during resizing and whether or not it needs trimming.
 
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