Lake City brass for .223

[ATLDave]

I'm interested in the wisdom of the forum on what adjustments should be made to load data when the brass being used for a .223/5.56 is Lake City, as opposed to Remington/Winchester/etc. commercial brass.

"Start over and work up" is an OK response, just trying to figure out if I should assume max is lower and not even bother with it; I don't load over book max since I don't trust myself to read "pressure signs" without failure.

 

[W.E.G.]

I have measured the water-volume of LC and commercial .223/5.56 cases, and I cannot discern one iota of difference.

Based on my measurements, the commercial cases actually held LESS water.

That is if 0.1 grains is actually a measurable amount of water under the conditions of holding a case under the tap, and then pouring the contents into the pan of a scale.

I operate on the theory that case volume is identical in all .223/5.56 cases of the same length.

Where you need to be careful is with some commercial cases.
The brass of some commercial cases is markedly inferior to LC cases, and simply should not be reloaded under any circumstances.
Some years ago Federal ran a batch of cases with "large font" FC marking, and no year-marking.
That brass was barely fit for the first firing, and definitely unfit whatsoever for reloading.

Segregate your brass into lots of "times-fired," and inspect the lots closely before sending any particular lot through another round of loading. Use of a hand-priming tool will greatly help in detecting whether primer pockets are becoming loose. Visual inspection of the inside of the case for "stretch rings" (which often may not be visible on the outside of the case) is very important. Good reading glasses and an LED flashlight with a narrow-focus beam are essential for trying to peer into a .223 case.

 

[beatledog7]

I load all my .223 to about 95% or less of max, so provided the brass interior volume varies by less than 5%, I'm good.

 

[ATLDave]

Great info, W.E.G. The heck of it is, my rifle is so hard on brass* that if I can reload it even once, I consider myself lucky. (Unfortunately, that same it has a marked preference (accuracy-wise) for heavier bullets. Thus, while my home-rolled cartridges with new brass are pricey compared to bulk 55 gr stuff, it's still cheaper than buying the stuff with Sierra Match King bullets already loaded.) So case longevity isn't too much of an issue; no brass has much longevity for me!

* Even at starting loads, the brass gets dented by the ejection process, and the extractor often gouges the rim to boot.

 

[animator]

Great info, W.E.G. The heck of it is, my rifle is so hard on brass* that if I can reload it even once, I consider myself lucky. (Unfortunately, that same it has a marked preference (accuracy-wise) for heavier bullets. Thus, while my home-rolled cartridges with new brass are pricey compared to bulk 55 gr stuff, it's still cheaper than buying the stuff with Sierra Match King bullets already loaded.) So case longevity isn't too much of an issue; no brass has much longevity for me!

* Even at starting loads, the brass gets dented by the ejection process, and the extractor often gouges the rim to boot.

If an AR-type rifle is damaging cases on extraction to the point they are not re-loadable, it sounds like there is an issue with the gun that should be addressed.

 

[W.E.G.]

There are things you can do to reduce the damage on ejection.

Consider changing the extractor insert (blue vs. black), or change the buffer weight, or even put a small bevel on one side or the other of the extractor claw.

A case catcher and/or deflector - goofy and obtrusive as they can be - might save a lot of your brass when you are just playing around at the range.

If you have one of those shorter-barrel AR's you may be stuck with it damaging brass at least to some degree. I noticed that when I had a 10.5" upper, it was pretty hard on case rims.

 

[ATLDave]

It's not an AR, it's a Sig 556, which have a reputation for being hard on brass. But I may try to tweak something.