.223 sizing die setup/headspace issue

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soam

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I have a Hornady LnL AP press, RCBS small base .223 sizing die, and am using Frankford Arsenal case lube. I have a Lyman case length headspace gauge, which I have tested with some factory ammo and seems to work correctly.

Initial sizing die setup was done according to the directions that came with it. I ran the ram all the way up (handle all the way down), screwed the die in until it touched the shellplate, then lowered the ram and screwed the die in an additional 1/4 turn or so.

Sized cases were winding up with too much headspace - the case head sticks out over the upper step of the gauge pretty obviously. I lowered the die an additional 1/4 turn, which causes the bottom of the die to really press hard against the shellplate at the top of the stroke, but the cases are still borderline. I put a metal ruler over the top of the gauge, and it still barely comes in contact with the case head, so at best I am right on the edge of maximum headspace. I tried lowering the die further, but the amount of force required to push the handle to the end of the stroke becomes excessive at that point.

Do I just have a faulty die, or is there something I'm doing wrong?

Edit: I took one of the sized cases that was under 1.76" long and seated a bullet in it, then loaded it into a mag and chambered it in my AR. It chambered fine and ejecting it was not an issue. Can I assume it's safe to go ahead and use the setup I have?
 
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Supermoto said:
How much are you bumping the shoulder back?
Click to expand...

Not sure, I'm not measuring dimensions, just using the headspace gauge to check whether the case is in spec. The goal is to make general-purpose plinking ammo for ARs, but not necessarily for a specific rifle, so I want the ammo to be in spec for .223. After doing more research, I've read that the Lyman gauges are somewhat suspect, so I'm going to try getting an L.E. Wilson gauge before I proceed further. Unfortunately every place I've looked is out of stock on the L.E. Wilson .223 gauges.
 
Get an RCBS Precision Mic. You can use it to measure the shoulder-to-casehead distance before and after, and it's calibrated so you can set the die to size to SAAMI 0.
 
Hornady is cheaper and can do multiple calibers.

The OP indicated that he wanted to load a single caliber for multiple rifles, and ensure (or at least maximize the possibility) that the ammo will chamber in 'all rifles'. In other words, he wants to make factory-like ammo. The RCBS Mic is calibrated so you can take an absolute measurement and set the headspace to SAAMI zero.

The Hornady gage allows you to do multiple calibers, but it's a relative rather than absolute measurement. You measure the casehead-to-shoulder distance of a case fired from your rifle, then set the sizing die to push the shoulder back an appropriate amount. You can still use it to make ammo for every one of your rifles - just measure the case from the rifle with the tightest chamber, and push that shoulder back 0.003". The ammo will work in all of your rifles.

I use the Hornady gage. It's half the cost of a single precision mic (which is cartridge-specific), and can do many calibers.
 
EddieCoyle said:
Hornady is cheaper and can do multiple calibers.

The OP indicated that he wanted to load a single caliber for multiple rifles, and ensure (or at least maximize the possibility) that the ammo will chamber in 'all rifles'. In other words, he wants to make factory-like ammo. The RCBS Mic is calibrated so you can take an absolute measurement and set the headspace to SAAMI zero.

The Hornady gage allows you to do multiple calibers, but it's a relative rather than absolute measurement. You measure the casehead-to-shoulder distance of a case fired from your rifle, then set the sizing die to push the shoulder back an appropriate amount. You can still use it to make ammo for every one of your rifles - just measure the case from the rifle with the tightest chamber, and push that shoulder back 0.003". The ammo will work in all of your rifles.

I use the Hornady gage. It's half the cost of a single precision mic (which is cartridge-specific), and can do many calibers.
Click to expand...

Thanks for the info. If I do get the Hornady gage and figure out which rifle has the tightest chamber and set the sizing die to push the shoulder back 0.003" from that, is it possible for a case sized with the die to not "pass" the headspace check with a case length/headspace gauge? In other words, if my rifle has a relatively "loose" chamber, can I wind up with ammo that feeds and functions well, but is technically "out of spec" as far as headspace length?
 
EddieCoyle said:
Hornady is cheaper and can do multiple calibers.

The OP indicated that he wanted to load a single caliber for multiple rifles, and ensure (or at least maximize the possibility) that the ammo will chamber in 'all rifles'. In other words, he wants to make factory-like ammo. The RCBS Mic is calibrated so you can take an absolute measurement and set the headspace to SAAMI zero.
Click to expand...

Does the Dillon case gage do the same thing, only in a go/no-go measurement?
 
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I just ran into a similar issue last night sizing 5.56 cases which stopped fitting into my dillon gage correctly. I took a piece of newspaper out and twisted it into the case gage and wiped out a bunch of case lube and what looked like a few pieces of squashed down walnut media. Everything that gaged wrong fits fine in the gage now.
 
mlaboss said:
Thanks for the info. If I do get the Hornady gage and figure out which rifle has the tightest chamber and set the sizing die to push the shoulder back 0.003" from that, is it possible for a case sized with the die to not "pass" the headspace check with a case length/headspace gauge? In other words, if my rifle has a relatively "loose" chamber, can I wind up with ammo that feeds and functions well, but is technically "out of spec" as far as headspace length?
Click to expand...

Yes. It's unlikely to be the case in a decent modern AR, but it's not unusual to see this in older milsurp rifles.

rutilate said:
Does the Dillon case gage do the same thing, only in a go/no-go measurement?
Click to expand...

It's a go/no-go.
 
Don't lose sight of the fact that you should trim all sized cases. Full length sizing and bumping the shoulder back is good, but you also have to avoid any risk of pinching the neck/case mouth of the case into the rifling. Some range brass I have processed over the years showed rings of brass missing from the case mouth. Trim to 1.750 and you'll never have any issues with that.
 
With the Lyman/Dillon/LEWilson gage, you can also insert the bullet base-first to detect a burr or malformity around the rim/extractor groove that could be all that is preventing proper gaging of your sized case. Same can be done with the mouth end. Let's say you have a properly sized case with a damaged/flared mouth. This could also not allow the case to gage properly, even though your shoulder could be just perfect.
 
EddieCoyle said:
Hornady is cheaper and can do multiple calibers.

The OP indicated that he wanted to load a single caliber for multiple rifles, and ensure (or at least maximize the possibility) that the ammo will chamber in 'all rifles'. In other words, he wants to make factory-like ammo. The RCBS Mic is calibrated so you can take an absolute measurement and set the headspace to SAAMI zero.

The Hornady gage allows you to do multiple calibers, but it's a relative rather than absolute measurement. You measure the casehead-to-shoulder distance of a case fired from your rifle, then set the sizing die to push the shoulder back an appropriate amount. You can still use it to make ammo for every one of your rifles - just measure the case from the rifle with the tightest chamber, and push that shoulder back 0.003". The ammo will work in all of your rifles.

I use the Hornady gage. It's half the cost of a single precision mic (which is cartridge-specific), and can do many calibers.
Click to expand...

There seems to be two similar (at least in my eyes) Hornady products. They have a headspace comparator and a Headspace gauge tool. I'm pretty sure you are talking about the headspace gauge tool, correct? What would be the difference between these two items?

For completeness, this is the RCBS Precision mic that you mentioned. Correct?

BTW: I have taken you basic reloading class, does the rifle class cover the use of these tools?
 
Alright, I've placed an order for the Hornady Headspace Gauge kit (this one) and will do some comparisons between fired cases and sized cases before I proceed any further. I have to wait to do more anyways since the next step is trimming, and my trimmer is still on order.

Thanks for the info!
 
dans said:
There seems to be two similar (at least in my eyes) Hornady products. They have a headspace comparator and a Headspace gauge tool. I'm pretty sure you are talking about the headspace gauge tool, correct? What would be the difference between these two items?

For completeness, this is the RCBS Precision mic that you mentioned. Correct?

BTW: I have taken you basic reloading class, does the rifle class cover the use of these tools?
Click to expand...

The first link you posted is for the Hornady Bullet Comparator. I have that, plus the inserts for checking headspace (your second link).

That is the RCBS Precision Mic that I was referring to, and the prices have come down. I think I paid $75 for mine not too long ago.

I bring and cover the use of these tools in the rifle class.
 
Is it possible to use a wilson case holder to index the shoulder of a 223 shell to measure the length in preparation for sizing back to SAAMI zero?
I'm anxious to get started and not willing to wait for my Hornady head space gauge.
 
After reading this thread I, of course, ran out and got the RCBS Precision Mic.

But, I'm getting very inconsistent readings. I'm using an RCBS Small Base die for .223 Rem. After lubing a bunch of cases, I mic one, and if it's greater then SAAMI 0 I run it through the sizing die. The finished product is not consistent however. Some seem to be the same as when they started and some end up less than SAAMI 0.
 
Knuckle Dragger said:
After reading this thread I, of course, ran out and got the RCBS Precision Mic.

But, I'm getting very inconsistent readings. I'm using an RCBS Small Base die for .223 Rem. After lubing a bunch of cases, I mic one, and if it's greater then SAAMI 0 I run it through the sizing die. The finished product is not consistent however. Some seem to be the same as when they started and some end up less than SAAMI 0.
Click to expand...

Is the brass sorted by headstamp and all fired from the same rifle?
 
EddieCoyle said:
Is the brass sorted by headstamp and all fired from the same rifle?
Click to expand...

No. I thought I was controlling for that variation by measuring everything before sizing and only using > SAAMI 0 cases to calibrate my die. They all start out different, but shouldn't they end up the same after sizing assuming that they're greater than SAAMI 0?
 
I'm using an RCBS Small Base Die in a Dillion 550. It's not so much the variation as it is the inconsistency. Some cases are only + 1 or 2 and come out pretty much where they start. The occasionally one comes out -4 or 5. I would be helpful to understand what tolerance I should expect. What I'm seeing may well be withing acceptable limits.

But, I am at a standstill at the moment because I got a case stuck in the die. D'oh!
 
Knuckle Dragger said:
I'm using an RCBS Small Base Die in a Dillion 550. It's not so much the variation as it is the inconsistency. Some cases are only + 1 or 2 and come out pretty much where they start. The occasionally one comes out -4 or 5. I would be helpful to understand what tolerance I should expect. What I'm seeing may well be withing acceptable limits.

But, I am at a standstill at the moment because I got a case stuck in the die. D'oh!
Click to expand...

I bet it's the press and dies. With small base dies, you need to apply more force to get the case into the dies, and exactly how much force depends on the case. With mixed brass, I bet you can tell that different headstamps require more or less force (if you don't believe me, size a PMC case and then a Lake City case).

A progressive press like the 550 (also some turrets and c-frame single stages) will flex more than a solid-frame single. The amount of flex is going to be determined in part by the amount of force applied. Different amounts of flex will cause the casehead-to-shoulder didtance on sized cases to vary.

I saw this when I prepped brass on my progressive. It went away when I started using a solid "O" frame single stage to size my rifle brass.
 

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