Case body resizing issue

[Cokie]

I've been trying to perfect my case resizing but I am having a hard time figuring everything out. When I load the resized case into my rifle's chamber it is pretty tight. If I drop the bolt it goes into battery and I can pull it out without much effort, so not too tight to not chamber, but I am hoping to get it to slide in easy like factory ammo. I believe the problem is the case body width is not sizing down enough or is springing back to chamber dimensions.

Using Hornady Calipers and Hornady's headspace gauge kit, using factory unfired and fired Norma 223 ammo, I get a base to shoulder measurement of 1.452 inches. Brass that is fired from my chamber measures 1.457 inches. The brass after resizing in my RCBS FL 223 die measures 1.452 inches. I do not believe the issue is related to the length from base to shoulder. I have been using case lube on the expander ball and inside the case necks, so I don't think the expander ball is pulling the shoulder longer. I have no good consistent way to measure shoulder datum so despite my thoughts, it may be causing the problem.

When I put my calipers around the body of the cases near where the sizing die ends, the factory ammo measures .372 inches, the fired brass measures .374 inches, and the resized brass just under .374 inches. I can't measure exactly the same place on all the cases, but I am pretty sure the measurements are reliable enough to tell me something.

I am camming over just a bit on the press, and the shell holder makes contact with the bottom of the die. I don't think I can size down farther on the case and even if I could, I don't want to bring the shoulder back farther since its already .005 bumped back. Do you think the 2 thousandths on the body will cause the cases to not slide into battery easy, maybe I should try a small base sizer? or what else can I do?

[5.56 Bonded SP]

This is what you seek.
https://www.midwayusa.com/product/45...-223-remington
Just drop your brass in it, and it will show you if it is too long, too short, or within spec.
I don't trust myself trying to measure the shoulder with calipers, too many variables. This tool or one like it is the easiest way for me.

ETA: that little tool shows you if it is within spec for case length, and shoulder length. It is really handy, and fast.
I resize all my cases every time I reload them.

[T2C]

It sounds like you need to buy a full length sizing die. I had a similar issue with sizing .308 brass fired in semi-automatics and the full length die resolved the issue.

Some brass requires more than one trip through the resizing die and some does not. You will learn through trial and error which cases spring back and require two passes.

[Cokie]

I am currently using a full length die. So another pass may squish it back down? I'll give it a try. That would be awesome if that's all it took.

[fedupflyer]

Remove the expander ball when setting up a sizing die (and maybe not use it at all). Sometimes the expander ball will compress or stretch the neck. I even have it happen on my Forster press using Forster dies with a polished ball. It will cause you to chase your tail if you are using the Hornady compararator. Ask me how I know.
I have now moved to a expander mandrel for precision ammo.

Consistency equals accuracy.

[Coal Dragger]

I am currently using a full length die. So another pass may squish it back down? I'll give it a try. That would be awesome if that's all it took.

You should invest in a case gauge, the one linked to will work great. If your cases are not in spec with your current die setup you may need to try a new die. A small base resizing die may also make a difference for you.

[bigedp51]

Not all case gauges are created equal and have a body diameter at Max SAAMI diameter.

Below the cases were inserted base first in a Wilson, Dillon and JP Enterprise gauge. And as you can see the red JP Enterprise gauge is a smaller diameter.

Bottom line if the resized case fits in the JP Enterprise gauge it will chamber in any rifle.



A resized case for a semi-auto should be .003 to .005 smaller in diameter than its fired diameter measured at three points along the body of the case. This gives the case more "spring back" from the chamber walls when fired and more reliable extraction.

A small base die will reduce the case diameter approximately .002 to .003 and also bump the shoulder back more than a standard die.

"BUT" dies can vary in size, example I have a standard Lee full length .223 die that will reduce the case diameter more than my RCBS .223 small base die does. And my RCBS small base die only reduces the case diameter .001 more than my standard RCBS .223 full length die. So again resizing dies can vary in diameter and shoulder location, so check your fired and resized case diameters.

And some commercial .223 cases have thinner and softer brass in the base of the case and may need to be sized with a small base die. I buy bulk once fired Lake City brass and all of it is sized at least once with a small base die to bring the cases back to SAAMI minimum dimensions and counter act brass spring back after sizing.

[markm]

Case gauge ALL THE WAY. Takes all the nonsense measurements out of the way. And get rid of the expander ball, and buy a neck expanding die. Expander balls are brutal on your brass/necks, and leave too much runout in the neck.

It's an extra step, but the neck expander die is worth it if you are serious about your loads.

[bigedp51]

Below a Lyman type "M" expander and the main part of the expander is .003 smaller than bullet diameter for more bullet grip. Also bumping the case mouth on to the .226 step aids seating and reduces neck runout. The RCBS AR series dies have a taper crimp and you just bump the case into the crimping die to streamline the case mouth or add more bullet grip. (If needed)

NOTE, with brass spring back after expanding the case mouth onto the .226 step you will not see and case mouth expansion and may not need the taper crimp.

[HKGuns]

Another vote for the case gauge.

Best advice I ever received when starting to load rifle.