New reloader, question on bumping the shoulder back

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MrSpiffy

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I'm just starting on my first batch of brass, having never reloaded before. And I'm running into questions that I want to make sure I have answers to before I continue. This post might get a bit long, so my apologies in advance for being long-winded, but I want to present all the information I have in case it helps.

Some background:
  • Ammo to be loaded: .223 Remington, for use in an AR-15 with .223 Wylde chamber
  • I've already cleaned my brass, using a solution of water, white vinegar, and a bit of dish soap.
  • Scrubbed the inside of all case necks
  • Neutralized the acid using a very mild bleach solution
  • Strained out the cases and dried them out in the oven at 200°F for ~45min
As I started the case lube process, I tested a few cases on my press (Lee Breech-Lock Hand Press with Lee Pacesetter .223 dies). I set up the decapping and sizing die per the instructions, then checked to see if it bumped the shoulder back on my cases at all by using a Hornady Headspace Gauge. Initial fire-formed measurements of handful of pieces ranged from 1.461" to 1.463" to the datum line. These pieces were from three different brands of ammo, all once-fired: Hornady Match, PMC Bronze, PPU, and Winchester white box 5.56mm.

After sizing a couple of cases, I noticed the shoulder didn't move, so I turned the sizing die down a small amount and tried again. This time it started to bump the shoulder a bit on one case, but not the other. One case bumped back to 1.459", while the other stayed at 1.461".

I then checked to see if either would chamber in my AR, and the 1.459" does just chamber, with the lugs locking. The 1.461" does not fully chamber. So, now I have an idea of how much headspace I have in my gun. And, from what I've read, I need to bump the headspace back somewhere between 0.002" to 0.004", depending on who you ask. So, my target is 1.456".

I then sized a total of 6 cases. Out of these, 2 bumped back to 1.456". The others bumped back to 1.452". The two longer cases were PPU and WWB, while the shorter cases were Hornady and PMC.

Is it normal for some cases to get bumped more than others? Is this typically related to brand? (Long and short cases had no overlap in brand, so far, but my sample size is tiny) Or does it just vary randomly? And what's the best way to proceed forward from here?

Thanks in advance for any advice you might have. :)
 
It will vary some randomly. When you say AR it makes me assume your talking about an auto. With an auto you'll want to give a little extra space for ease of feeding. Try to reproduce factory specs.
 
MrSpiffy said:
<snip>

I then sized a total of 6 cases. Out of these, 2 bumped back to 1.456". The others bumped back to 1.452". The two longer cases were PPU and WWB, while the shorter cases were Hornady and PMC.

Is it normal for some cases to get bumped more than others? Is this typically related to brand? (Long and short cases had no overlap in brand, so far, but my sample size is tiny) Or does it just vary randomly? And what's the best way to proceed forward from here?

Thanks in advance for any advice you might have. :)
Click to expand...
Maybe the two shorter ones were that way to start and were unaffected by the setting for longer.
 
RealGun said:
Maybe the two shorter ones were that way to start and were unaffected by the setting for longer.
Click to expand...

I can confirm that at least one of the shorter cases was at least 1.461" prior to resizing.

I'll measure some factory ammo to compare.
 
Headspace is a static mechanical measurement built into the firearm. For a bottle necked cases head clearance is how much slop we have between the case head and the breech when the case's shoulder is forward against the shoulder of the chamber. We can make too much head clearance by over sizing and creating an unsafe "headspace" condition in a perfectly fine chamber. We often call it headspace, but it's really just too much head clearance. I sometimes call this "artificial headspace", but again, it's just excess head clearance. Too much mechanical headspace built into the rifle, or too much head clearance from over sizing can create a dangerous situation, and will cause incipient case head separations in a shot or two, maybe three, depending on how bad it is.

You need some way of measuring where the fired case's shoulder is before and after sizing. Then you want to move the shoulder an average (Because yes, different cases resist sizing and spring back more than others.) of .003 to .004 for good function in an auto. Or size it to fit a case gauge like the Wilson or Sheridan. The Wilson measures case length and shoulder position but not diameter, while the Sheridan does diameter as well. Handy items for the reloader.
 
Thanks, guys.

So, will my new clearance of 0.007" on these few cases be too much? Or should those cases still be okay to use this time around?

I'll try to size a little longer and reduce it a little at a time to get what I want. I'll also try sizing separately by brand to see how that affects dimensions.
 
Are you saying you are going to move the shoulder back .007, or have you measured the head clearance of a chambered case at .007?
 
I already sized 6 cases, 4 of which ended up being bumped back 0.007". I'm asking if I can use those, or if I should toss them.

I have about 130 more cases that haven't been sized yet. I'll resize the rest of the cases to be bumped only 0.003" to 0.004" back.
 
Plenty of .223 is safely reloaded and fired in ARs without ever measuring with a comparator or any other kind of case gauge. Don't overthink this thing.
 
I would scrap those. I recently sold $42 worth of scrap brass cases. That was stuff from a number of years, but hey, it beats throwing it away. :)
 
As an engineer, that's exactly what I tend to do, over-think things. But I'd rather be safe when I have small explosions happening near my face. And being new, I just want to cover all my bases.
 
Well, then, from one engineer to another, I'm telling you, don't overthink this. When I was new to reloading, I loaded and shot a pile of .223 through my first AR before I ever got my comparator or Wilson gauge. I just FL sized it in a cheap Lee die according to the instructions and rolled on.
 
As an Engineer, I would think he would want to study up on chambers, headspace, head clearance, and know exactly what is happening with his reloads.

But yes, the gun makers and die makers do a great job of keeping us out of trouble if all we do is just screw the sizer down all the way and go our merry way, which is what a lot of folks do, and what I did as well when I first started out. :)
 
I've definitely done a lot of reading, searching, and video watching. The concept here is pretty simple, but it involves an element of danger. Sounds like I'll probably be okay, but I'll watch more carefully in the future.
 
Walkalong said:
As an Engineer, I would think he would want to study up on chambers, headspace, head clearance, and know exactly what is happening with his reloads.
Click to expand...

I think he has. So much that he has now sized cases that won't chamber in his rifle. All the concern for a precise .004" bump has actually created a problem. By "don't overthink it", I mean to say that if the shoulders aren't moved back enough and the cases won't chamber, just screw the die in some more. It really is that simple.

He's essentially using his chamber as a case gauge, which is fine. What would I do if I sized some cases and they wouldn't fit in my Wilson gauge? Well, I'd screw the die in and size them some more. :D
 
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Thanks, guys! Turns out my problem was adjusting my die without relubing the case again. It got harder to remove from the site, resulting in stretching the neck out again sometimes. This made it hard to get consistent, and made me think I had to adjust the die down farther again.

Adjusting the die after adding more lube each time got me squared away. Now all of my cases sized fine with the same setting, resulting in a 0.003" to 0.004" bump of the case shoulder.

Nothing like learning by doing! And I greatly appreciate all of your feedback and suggestions!
 
Thanks for the advice. :D

The more I do something, the easier it usually gets. Looking forward to finding a good load for my AR.

And Happy New Year!
 
MrSpiffy said:
Thanks for the advice. :D

The more I do something, the easier it usually gets. Looking forward to finding a good load for my AR.

And Happy New Year!
Click to expand...
Me too, but there again I am keeping it simple. I look at the jar of H335 and deduct 10% from what it indicates for 223. It is a narrow range, and this is not precision rifle, so I expect I will be able to stick with this load.
 
That press is so light duty that the flex in it isn't going to allow you to stay within the +/- .0005 you say your getting. Unless your pushing against a stop (shell holder). There is going to be more difference in the brass then that also.

If your using the same brand die & shell holder you will end up with safe ammo shoving the brass as deep into the die as the shell holder will hold. You could possibly create unsafe ammo by trying to predict how much flex that hand press is going to create trying to maintain .003". Do yourself a favor & bump the shell holder until you get a better press anyhow. The Lee Classic Cast BL is a nice sturdy press. However for autos I still just bump the shell holder as per instructions from the ones that know best about their tool.
 
With stiffer conventional presses that use standard shell holders with a .125" height reference, using Redding's Competition Shell Holders in .002" steps in height above that lets you pick one that when the die stops its stroke, the resultant case headspace is a couple thousandths short of the chamber headspace. And such sized cases are very uniform in headspace; often varying less than a .001" spread.

Two things that let more flexible presses cause sized case headspace to vary. One's how much the press flexes. The other is how much lube is on the cases coupled with how long the case is full into the die. If there's clearance between die bottom and shell holder. the press will slowly contract and size the case a couple thousandths more while you hold the lever and ram still.
 
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@kingmt, I had one here or there that varied out to 0.005" bump. But overall, it was pretty consistent. I checked every case initially, then every few cases after getting dialed in, then every 10 cases or so as I got comfortable to make sure nothing was wandering.

@Bart B., I tried to be consistent in the amount of case lube I used on each case, how I applied it, and I got into a rhythm for my pace when closing and opening my press. Probably explains why my results were fairly consistent, also.

My long term goal is consistent, accurate loads for each of my guns. I know this press is entry-level, and it's going to flex a bit. But it's a good place to start and see if I enjoy this hobby before investing in something more expensive.
 
MrSpiffy said:
I tried to be consistent in the amount of case lube I used on each case, how I applied it, and I got into a rhythm for my pace when closing and opening my press. Probably explains why my results were fairly consistent, also.
Click to expand...
I have a foam lined coffee can I put a few drops of case lube in then tumble 50 cases to lube them. Cases are quite uniformly lubed and when I finish full length sizing the 50 cases from the last batch, the batch in the tumbler's ready for sizing.

My case lube is a 50/50 mix of STP engine oil treatment and Hoppe's No. 9 bore cleaner.
 
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