Works for me

V

velocette

New member
I want my AR rifle's brass to last a long time. I got tired of case mouth splits after 3 or 4 reloadings. I did not want to get into case annealing. So, I examined how the brass was resized. With a standard full length resizing die, the neck is squeezed down by the die and then pulled back out to the "correct" size by the expander ball. This works the brass twice, thus work hardening the case neck, getting it ready to split sooner.
Therefore, I invested in a neck sizing die and a case sizing die. The neck sizing die squeezes the neck down to a proper diameter & does not touch the case body. Then full length sizing with the body die which does not touch the neck.
The result is that the neck is only worked once and it is worked as little as possible.
Another advantage to this method is that case trimming to length is needed much less. This is because when the expander ball is pulled back out of the case, it works to lengthen the case. Something you can feel the effort as you pull the expander ball out.
Another assist toward long case life is by measuring 15 or 20 of the fired cases using a Case measuring tool, then averaging the results.

https://www.midwayusa.com/product/4...headspace-gauge-5-bushing-set-with-comparator

Then adjusting the case sizing tool to bump the shoulder back 1 ~ 2 thousandths less than the average of the as fired & locking the die ring in place.
What you are doing is adjusting your reloading dies to work the brass as little as possible and still chamber properly.
A side benefit can be better accuracy as the cases fit your chamber almost perfectly.
Please note that this case die adjustment is only for the rifle you set the die up for or ones that have similar case dimensions.
If this does not work for you, I'll refund what you paid for this advice.
 
I've had excellent results sizing the bodies with a Redding body die and the necks with a Lee Collet Die (takes some getting used to, but is great once you have). The necks stay essentially perfectly concentric with the body. No expander is needed. The mandrel prevents internal donuts from forming.
 
Working the brass is the main reason I have gone to Lee Collet Dies for most of my reloading. Cases really do last longer.
 
FWIW, Redding makes a bushing type FLS die that does body and neck sizing (and decapping) in one operation without the need for a neck expander. Other mfrs. may also make them, I don't know. I don't load/shoot enough rifle to justify the die, but for those wanting a bushing type neck sizer, it would save a space on the press if that matters to them.
 
Two things come to mind,
One is a chamber that allows neck to blow way out.

The second is a resizing die that OVERCOMPRESSES the neck, making the expander ball overwork the neck bringing it back to a size that will hold the bullet you are using.

That work hardens the crap out of the neck!

A fired case should just allow a new bullet to fit.
If it drops in with a lot of slop, the chamber needs to be corrected.
This isn't a hard or expensive deal with a good gunsmith.

The second thing is to hone out the neck of the die so it only compresses enough to regain neck tension,
Then hone expander ball for precise final fit for the bullet.

Annealing is the ONLY way to soften the brass,
But about 99.9% of home annealed brass is done wrong, changing the properties & pliability/workability of the brass...

Overheating is a HUGE deal, and most 'Home Made' flame annealing is done wrong...
Research is paramount when doing annealing, but that's another thread...
 
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A fired case should just allow a new bullet to fit.
If it drops in with a lot of slop, the chamber needs to be corrected.
This isn't a hard or expensive deal with a good gunsmith.
Click to expand...

Could you elaborate on the process of correcting an OVERSIZE chamber neck??

The only way I know of to correct an oversize chamber is to remove the barrel, cut off enough of it, rethread, reinstall in the action, and recut the chamber to the desired specs.

That is NOT something I put in my category of "isn't hard or expensive". It is precision metal work, requiring special tools and a degree of skill. A good gunsmith can do it, sure, but it isn't going to be "cheap" by my standards.

If you know another (better?) way, enlighten me, please.

Correcting an UNDERSIZE chamber is comparatively simple and easy. Taking metal away usually is. Putting it back, gets complicated and costs a bit more...:rolleyes:
 
IME, a fired case from a tight rifle chamber neck diameter typically does not let a bullet drop in. The mouth is usually curled over a little at the end and has to be expanded. If the neck portion of the chamber is loose, then it will expand enough to let a bullet drop in.

Neckcurledin_zps085e0876.jpg
 
This might get a little technical,
Its as easy as moving the barrel backwards slightly.
In a lathe, you simply add a couple extra threads, shave a little off the chamber end,
This moves the chamber backwards so there is material to remove.

Then you simply use a chamber cutting tool, reamer or actually cut the chamber to specification.

This often clears up a lot of problems, chambers that have been cut at an angle to the bore, chambers that are cut oversize, chambers that have way too long throats, ect.

The quality of barrels, Especally chambers in semi-auto rifles are horrible much of the time and a quick clean up really makes a difference.

I align between centers of the BORE, the actual rifling bore, so when I cut the threads/chamber they are SQUARE/ALIGNED with the bore, not the outside profile of the barrel.

Most guys will get along fine with an off the shelf, high quality chamber reamer,
Someone that wants tight tolerance chambers might have to use two or three cutting tools to get exactly what they want.

When you have seriously tight tolerances in the chamber, it pretty much precludes shooting 'Surplus' or 'Cheap' ammo, since the thickness of the neck material (brass) can be all over the place in 'Cheap', Import or brass of unknown origin, often too thick for proper chambering.

I cut mine just large enough for most US made commercial brass and leave it at that. I don't want to spend a ton of time turning neck wall thickness on what started as substandard brass to begin with,
But US manufacturers stick pretty close to SAAMI specifications in case wall thickness...

For example,
I don't want a 0.224" bullet dropping into a case that was blown out to 0.250" or larger, just too much overworking of the brass to bring it back to specification to hold a 0.224" diameter bullet again very many times without splitting...

Its pretty simple to chamber a barrel correctly to aid in reloading, and yet NONE of the manufacturers seem to pay attention to the details...
If I'm building the rifle from scratch, or I have the barrel off for any reason, it takes about two hours to chuck it up in the lathe, square up the mating faces, add the extra threads, knock off the same (thread) amount off the back of the barrel, and correct the chamber.

I just did one for a neighbor in an AR style rifle that had a chamber 5.5* angled to the bore, and the bore angled in the barrel stock 0.057" off center.
That barrel now is bent in an 'S' shape and holds my iron pot over the fire pit,
New barrel drilled/bored centered cost $66 and took two hours to fit to his action.

Throws brass with neck expanded to 0.2255" ID, and no more bent necks on the brass, bolt locks up solidly on all lugs...
With 'Carbine' barrels advertised for $33 when you buy a dozen or more, you can bet they were made in 'China' or somewhere they know nothing about heat treating and they are made on worn out 1950's machines...

Happiness is a well made, well fitted barrel!
 
A REALLY tight chamber won't allow for ANY variance in ammo builds.

I build my chambers to accept about any US made ammo.
I have bench rifles that won't accept anything but turned case necks, and that gets old FAST when you are talking range/practice ammo...
 
The guys shooting much volume with outside neck turned brass seem to be using the Gracey trimmer's neck turning cutter. Speeds it up a lot. I first saw that demo'd by the old Sinclair (before Brownells buy-out) at Camp Perry one year. Quick.
 
The picture Unclenick displayed looks to me like someone cut the chamber with a taper instead of a square shoulder at the end of the neck.
Don't know for sure, but it kind of looks that way since the outside of the neck is tapered and probably started with a square cut mouth since there are still factory chatter marks in the brass.
Tapered mouths don't show that chatter, it gets trimmed off during champerfing.

Once the gas jet following the bullet escapes, forward momentum creates a vacuum pulling the case forward, a short cut neck with a taper would produce a case neck that looks just like that.
I used to have some chamber cutters that were radius cut instead of square cut and the produced case mouths that looked just like that,
The reason I use square cut chamber reamers now, and also why I cut neck length on a lathe quite often in bench barrels.

The old thought was a square shoulder would allow a crack to form, but I don't hold with that old myth.
You would think in 45 years of doing this on every barrel imaginable ONE of the chambers would have failed if it were true, none so far...
 
The picture Unclenick posted is nothing more than a case that was not trimmed back enough. It does not matter if the end of the neck area is square, round, or tapered. If the chamber neck is too short or your brass too long, that is what it is going to look like. Almost all chamber reamers have an angle on the end of the neck. Quite a few DO have a tapered neck. Easy as moving the barrel back a couple threads? Where do people get this crap? I have been down that road once or twice. It affects everything on the fore end. If you have a screw in the fore end, it can turn into a nightmare. Now the stock fits like crap. You have to try to align extractor cuts and take them deeper. If you are lucky, the reamer you are using is almost identical to the one that cut the chamber. I can't see that as a "Quick fix". Make me wonder why you installed a new barrel on that rifle you were describing.
 
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