Ok. Before I hear how I can buy .222 brass I did this just because I could.

Reformed some 5.56 ar brass to .222 Remington. Ran them through the form/ trim die, trimmed down the necks, uniformed the neck walls to .013 and annealed the neck/ shoulder, matched base to shoulder measurements with factory new brass.

Found same case head stamps to vary in weight by up to 1 grain. Formed cases were about 10 grains heavier than factory.222 brass.

Used a starting load for the nosler 40 grain ballistic tip. Have had sub minute groups with this load in factory brass. Range trip showed formed cases to have same m.v. as factory brass with the same load data. Accuracy was less than desired, hanging in around 1.25 moa.

Lessons learned: reforming is time consuming, can work if supply of factory brass dries up or cost of new cases become too high. Few ar guys seem to save the brass. Cases will work ok for large varments under 300 yards when I am not concerned with losing the brass.

On top of the time spent it was kind of fun venturing into a new reloading arena

Forming brass is an education in itself. I did this for many years with cartridges like the .22 Long Snapper, .219 Zipper, .25-06 (long before it was a commercial cartridge). 338-06, .35 Whelen and the Improved version, .375 Whelen Improved, .411 Hawk and one or two others. Fascinating and enjoyable work many years ago, but now don't miss such work (especially annealing) or the guns.

I’m curious. Sounds like you did all the right things. I wonder why accuracy was mediocre. Neck tension fairly uniform? Runout of loaded cartridges in acceptable range? (0.002” or so at the neck) Did you have to trim a lot of material from the necks? Anneal before or after forming, or both?

I’ve threatened to try converting some .223 brass to .222 but never got further than pushing a few cases through a form-trim die, just to see what they looked like. I’m always interested in stuff like this.

I convert .223/5.56 to 6mm Mongoose, essentially a PO Ackey'd 6mm wildcat--should pushed back, taper mostly removed. It's kind of fun to really roll your own this way, but it's not for everyone. I've also made my own 9mm Mak from 9x19 cases and .30 Herritt from .30-30.

I'd suggest trying those cases again now that they are fireformed to your chamber.

The first time I did this was to make some 8X52 Siamese rounds for a rifle I modified for my wife. Started with 7.62X54 Russian and trimmed the neck back to 52MM then fireformed in the rifle. Loaded with 45gr of IMR4064 it tossed the bullet out the end of the barrel right smartly. I have no idea what the speed was or the muzzle energy but since the rifle was made by the Arisaka Arsenal in Japan I was not worried about the receiver blowing up. BTW I started with 40gr of powder and worked up to 46gr. I was seeing some pressure problems so cut back to 45gr and leave it there.

As to the accuracy issue from a proven rifle:

You've moved the neck down quite a way from the annealed portion of the 223 brass. You might try annealing those new necks, especially after all the work hardening that they've undergone from forming and thinning. It might uniform the release pressure of each case for a more uniform pressure build up.

By the way, I form 7.65 Argentine, and 35 Whelen out of Ought-Six brass. I anneal the necks after these operations and case life and accuracy is very good.

__________________
Keep your powder dry.

I’ve formed many wildcats and obsolete cartridges. Never had to form 222 from 5.56. Back when I got my first 223, it was #3 Ruger. I had some sources for GI 5.56 so I shot a lot of it. The old GI load was 55gr FMJ at 3250fps. I forget the reason but I used a syringe of water to fill a GI 5.56
& Rem 223. If I remember right the commercial brass volume was 5% more than GI. US GI brass differs a little, some of the imports differ a lot.

I'd first check case capacity (water weight) of the formed brass vs. regular .222 brass. Weight of empty brass alone often is no indication of capacity. The difference in actual capacity may be significant enough to where the powder charge weight needs to be reworked up or down to get approximately the same velocity you were getting with accurate loads. Of course, you'll need a chronograph to do this.

Runout is worth checking, but it would be the last thing I'd check and runout would need to be pretty significant to show an accuracy difference unless you have an incredibly accurate rifle, maybe a benchrest gun. Same for neck tension.

From 223/5.56, I form 30 Mauser, 7mm TCU and 300 Blackout.

Ivan

Just saying, the OP did indeed anneal the cases.

That he did. Missed it the first time around.

__________________
Keep your powder dry.

I do 351 Winchester from 5.56 and/or 300 Blackout. I have a pretty good supply of 351 brass but my OCD self kicks in when it comes to losing brass. And I once loaned the gun and 50 rounds to a friend, who spent the day shooting and came back without the brass.

If using 5.56 trim to length & size up to .351. If using 300 the case is a tad short. Extractor holds it in place.

Works very well.

After you check the case capacity of the newly formed brass you might want to also form fire the cases because I'm thinking the second reloading will be more accurate than the first after the reforming. Additionally, you might want to use new or only once fired brass to form the .222 cases. Again you may improve the accuracy if the brass wasn't well used or even abused before you reformed them.

I'm just thinking out loud. I have no proof this will work. It's just speculation on my part but it can't hurt anything.

__________________
Freedom is never free!!
SWCA #3437

You might consider using 222 Remington.

Ivan

You just never know what's going to happen these days ...
So it's great to have a back up plan to be able , if necessary , to form 222 cases from plentiful 223 . I would go ahead and lay in a supply of both while you can get them .
I would also do a back-up plan for bullets ... a bullet mould and a melting pot will allow you to cast all the projectiles you need when jacketed become too expensive or unavailable .
I have moulds for every firearm I own ... the day could come .
Gary

__________________
Certified Cajun
NRA Member

Years ago I would fire form .300 H&H to .300 Weatherby. The first time I think I closed my eyes, but it worked.

__________________
John

I think I would full length resize the once fired reformed brass, trim to length, and outside turn the neck to .011 or .012 thickness and go again.

"Weight of empty brass alone often is no indication of capacity."

Au contraire. If the external case dimensions are identical, the heavier case must ALWAYS have a smaller volumetric capacity. But maybe not by much. Think about it.

As the case shoulder is pushed back by re-forming a .223 case to .222, the final neck wall thickness of the re-formed case may be slightly thicker, and possibly enough thicker to require turning the neck to thin it.

Long ago, I did that .223-.222 case conversion without any problems But I have not had a .222 rifle for many years, sold my only .222 rifle (a Savage 340) nearly 50 years ago.

Perhaps I should have phrased that: case capacity is more important than case weight.

I wonder if different brass alloys could create the weight differences? Archimedes thought so. Internal volume, all other dimensions identical, may be the only valid determinant.

I'd expect that would work but the attraction of 5.56 is cheap and readily available. The 222 Remington case would still have to be cut & trimmed to 351 length. A 221 Fireball case would be about the easiest, case length is close enough to probably trim rather than cut & trim. But for not caring whether I get brass back or lose a few I think the 5.56 works best for me.

One of the issues with forming 223 into any other case is that just below the 223 shoulder is a case wall area that is variable in thickness. When I form either 300 Blackout or 30 Mauser, I FL size. I then trim to length & Inside neck ream (to .308"). This brings the finished neck wall thickness is around .010! (I use a Forrester "Original" trimmer, with a .308" ream instead of a pilot and a cordless drill at around 1000 RPM)

Also, LC military 5.56 brass has different wall thickness down around the case head. Brass for M-16 use is thinner than brass for belt fed use, by around .0004-.0005 inches. You won't be able to weigh the difference unless your scale can accurately weigh in .005 grains. The typical powder scale is +/- .1 grain and won't pick it up. I don't own a scale or tubular micrometer that can measure that small, but it is in the specifications.

The reformed 222 neck wall thickness will then have an inconsistency that cannot be corrected by neck turning. If you try by neck reaming, normal "Unsupported" reams must be at fast RPM's and the ream MUST be extremely sharp! Otherwise, it just pushes that bulge back to the outside. The old RCBS Neck Reaming dies hold the outside of the neck in place, so the extra thickness has no option but to be removed. It is an extremely time-consuming process!

Most varmint or hunting 222 Rem chambers are loose enough that none of this matters! Charge weight and bullet weight consistency are more likely the accuracy problem. A match chamber is a different story.

Ivan

4198 powder was originally (and still is) "the" .222 powder. My Sako (1950's sporter weight) prefers the 52 gr. Speer along with the 4198. Luckily I have plenty of brass, and in my 1st loading case prep uniform the primer pocket and inside debur the flash hole. The 2nd loading, neck size only, is trimmed if needed, and outside case neck turning (if needed). I usually count on 1/2 MOA or better accuracy.

__________________
H Richard
SWCA1967 SWHF244

That was my thinking when I bought my first mould. Then I actually used it and I've been shooting cast boolits in all my guns ever since.

Second firing. Cases were neck sized using the Lee collet neck size die. Reloaded with Sierra 52 grain Match Kings with H322 powder. Case necks had been annealed, provided very uniform .003" neck tension.

Lake City brass now shot less than 1/2 MOA. Big improvement from the first firing.

While time consuming, reforming cases has expanded my reloading capabilities and should there come a shortage on .222 or .221 cases, I am now confident I can reform them from available .223 brass.

Thanks to all who offered tips and tricks - they worked out!

Thanks for the update. Glad to know you were successful after the initial firing.

Annealing? ! ? For those with experience? !
Do you anneal before sizing/forming or at end of the process? Do you water bath after annealing or set it aside and cool naturally? In the past I have formed .224 Harvey K Chucks from 22 Hornet, 7mm TCU from .223, and .256-Win Mags from 22 Jet! All of these require firing forming to expand the necks. I have never formed by reducing the neck(357 Mag to .256 Win Mag because of the reaming required and the cost of the dies required!
jcelect

Great experiment. Sometimes it's not about should you do these things but can you do these things. Try reaming the mouth before you do your outside turning. I would ream, neck size, outside turn then neck size again. I am also a disciple of reaming the primer pockets and flash holes for my accuracy loads. This is important with military cases as there is a lot of variation. You will be surprised at how much brass you will be removing. I have never been able to get any other 22 center fire to shoot more accurately than the 222. They are really a great caliber. It's too bad it has fallen by the wayside. I've never done this conversion but I think I might have to give it a try. Just because I can.

I’ve always heard the old rule of thumb for annealing in case forming is anneal first when necking up (as in taking .30-06 to .35 Whelen, or something like that) and anneal after forming when necking down. I always drop my cases into water to stop the migration of heat, but really I think it’s more a matter of personal preference.

Without any sophisticated equipment to help analyze and control the annealing process, I’ve always consider my techniques pretty primitive, but I’ve had enough experience with it that I do quite a bit of it - and I think I’m doing myself some good. Like neck turning, opinions about annealing seem to be all over the place. In forming .222s from .223s, annealing shouldn’t be necessary, but it shouldn’t hurt, either. I’d definitely neck turn.

Just another opinion, not the basis for an argument...I haven't annealed brass in many years. I used the technique when forming .219 Zipper brass from either .25-35 or .30-30 brass. Annealing was the last of several steps. My methods were also probably quite primitive in comparison with what is done today. Annealing was allegedly necessary after all the cold-forming steps so that brass life would be a reasonable one. I think it helped in my situation, but don't know for sure. While the annealing process may extend brass life, I prefer to buy new brass when what I'm using is worn out.

Few annealed brass thirty or more years ago. Whether or not the process is as useful as some claim, I don't know but I do have some doubts. However, annealing done right likely does no harm. It does seem to have taken on some fad characteristics, but again, there may be something to it. I don't worry about "neck tension" if my rifle handloads are accurate.

As for neck-turning (outside turning, not reaming), I think this is of greater importance than annealing, at least from a safety aspect if for no other reason - and there are others. Neck-turning is a good bit of work but has never merited a fad status like annealing.

A good friend of mine has been working with an Australian firm that makes an electric annealing machine which can dial in exact temperatures, and they have formulas as to what temp is needed for all kinds of brass. They claim improved accuracy.

If anyone is interested, I can put you in touch with him. PM me if interested.

__________________
H Richard
SWCA1967 SWHF244