Can I form 204 cases from 222 Mag cases? If the shoulder angle does not match, can I fire form?

Thanks!

Absolutely. As I haven't recieved the CZ .204 I have on order this is a recommendation not a proven method, but it's how I'll do it when the rifle arrives and I do form a number of wildcats.

Back the .204 die out a ways off the shell holder, size the front of the case mouth to .204 leaving a .224 ridge around the juncture of the neck and shoulder. Size a bit then try to chamber the brass until the bolt closes with a crush fit, then load one with a light load. The crush fit will protect against excessive headspace that you'll undoubtly have if you just run a .222 Mag case in a .204 full length die.
Mic the neck on a loaded round, make sure there is enough room for the neck to open and release the bullet. Probably won't be a problem as going from .224 to .204 shouldn't interfere with a factory neck (they usually leave .008 to .012 room) if it's under .002 to .003 you'l want to turn the necks before firing, time consuming but a good thing for accuracy and case life.
If there's plenty of room have a mic ready and fire one round and immediately catch the warm case and mic the neck (mic em quick as they snap back quickly as they cool). If it's tight turn your necks, if not and the case is well formed (I'm betting it will be) form a few more cases and make sure they chamber with a crush fit then go for it.

This should be a very easy form job, hopefully you'll even be able to tighten up a sloppy factory neck a bit with thicker brass and turn em to clean em up a bit .

Well, from what I gather looking at all the hype about the 204 Ruger, it is nothing more than the 222 Rem Mag necked down and the shoulder blown out a little.

There should be no reason that you could not neck down 222 Rem Mag brass and fireform it. If you have a good supply of 222 Rem Mag brass already this might be a viable option.
Having said that, I imagine you could buy new 204 Ruger brass about as easy as you could 222 Rem Mag brass these days.

R F

I wouldn't count on the supply of .204 brass, I've heard they are claiming it'll be 2005 before they'll be able to supply em to reloaders. Plus whitch forming down .224 brass should give you a bit more material to work with in the neck, and room for a little turning while still tightening up a factory neck always a good thing.

Doug, I haven't tried to fireform any yet but I did run a couple thru the die and adjusted as normal, I got the little "ridge" you mention with simply running it thru and it will chamber! I guess I'll have to try a few! Buying factory loaded to get brass would be somewhat expensive!!! GHD

Hey GHD, it should be good and snug closing the bolt, if the bolt just drops you'll probably have excessive headspace. You've got to move the shoulder forward quite a bit in forming and need a solid stopping point to hold the case solid. Regardless of opinion just engaging the bullet into the rifling isn't enough, that said I'd still engage the rifling as added insurance.

I just put a factory .204 and a unfired .222 Mag case in a device calleed a precision Mic made by RCBS, you drop the case in a little cylinder and screw on the top that allows the neck to come through the top if the cylinder with the meassurement being taken from the bottom of the case to the datum line on the shoulder. This Mic is for the .223 but its functional for this test, in the test it shows .066 difference between the .204 shoulder (farther forward) and the .222 Mag shoulder, that's a lot of extra space and the case needs to be held firmly to give that case time to stretch and form to the chamber. I also will leave a bit of case lube on the cases (not the necks or shoulder, just the side and especially low on the case wall ) to facilitate the stretching and the metal moving forward.

MD, My first impression when looking at the 2 cases side by side was, "204= 222MAGAI, necked down! That's a pretty good bit of shoulder movement! Maybe I'll get a few tried today or tomorrow. I've got 100's of 222MAG brass since I've been shooting it and the 6x47 for nearly 30 years. LS&B and several other of the supply houses seem to have a good supply of 222MAG brass on hand.....at least they did a few weeks ago! GHD

GHD please keep me posted, as stated my .204 isn't here yet but I did pick up 500 .222Mag cases. I weight segregated the cases in lots of 50 did the primer pockets and flash holes, now I wait.
I'd be most interested in how it comes out, but as long as they are well supported in the chamber and the necks aren't too thick it should be a snap. Let us know how it shoots.
I'm most anxious to compare it to my Tactical .20, it has rapidly become my favorite rat rifle.

montdoug, Did the little test firing today! A 222Mag case FL resized in the 204 RCBS die adjusted as usual actually leaves the little "ring of 224" size neck. If you fire the case using a mid range charge of H4895 with the 40 grain VMax seated to contact the rifleing(2.405) you will see the primer start to back out.....just as you stated about the headspace! Now if you adjust the die as uual and then back off 1/2 turn, load the same forming charge, it will form a perfect case!! EXCEPT FOR LENGTH!!!!!! Hornady factory 204 rounds(either loaded with 32 or 40 grain) measured 1.843" after first time firing. The 222MAG cases (which measured 1.843-1.845 before firing) measured 1.866 after fireforming! That's a bit of stretch!!! I didn't have any brand new 222Mag brass to try so you may get different results with new brass! I think I'll just get another case or so of the factory stuff (32 grain) and use those cases. The factory 32 does in the .6's and my handloads do in the .3's so I guess the factory stuff will work for playing around and even a dogtown if I get out your way this year! Let me know your results! GHD PS: I shot 14 shots, 6, 32 grain factory and 8, 40 grain factory) just to get some more brass this PM in a pretty hurriedly fashion!!! Heat was still ok!!! Took the rifle into the cleaning room and proceeded to clean the warm barrel with MONTANA EXTREME checking for copper......practically nil!!! That was my experience also in breaking the barrel in.....not much copper fouling in this one!! GHD

montdoug,
Everything you told Sabot to do to get a good tight fit for fireforming is OK, but I don't like the idea of using a light load of powder. I'd load a full (Not Max) charge of powder. If you don't, you won't get the full formed case sometimes and you can tell when that is so by the primer slightly sticking out past the flush point of the case. Two things will cause the primer sticking out a bit. One is a light powder load and the other is not having the case "Crush" fitted to the new chamber properly or a combination of both a light powder load and an undersized case. Godsdog.

Good point, I should have said medium load. Actually I usually use a medium stout load to form, I just don't want to give someone advise that blows up their rifle. Note I was talking about the first case formed. With the sub-calibers I've seen some rifles over pressure with loads in the middle of the load charts. I always error on the side of caution, but your definitely right and once I've made sure of the safety factor I do load a fairly stout load to make sure the cases form well and I don't smoke the necks. I didn't finish the process, thank's for pointing that out.

Hornetfan: Green and Gold Rings are among my most favored colors also! I have had a run of great luck with my recent Remingtons that has lasted for at least 12 years and runs til right up to now! Virtually all of them I have bought and shot have been VERY easy to find accurate loads for! Mind you I have also bought in the last decade Rifles from Sako, Ruger, Winchester, Weatherby, Marlin and others as well as several Custom Rifles. Those Rifles from Big Green have all been accurate for me though - not like some brands I could mention. Most often those Remington Rifles were scoped with Gold Ring scopes. Pleasing combos those!

In your screens names sake I will repeat this "adventure" I had a with a Ruger Rifle in 22 Hornet!

I saw a Ruger #1-B in 22 Hornet at a Gunshow in Portland, Oregon several years ago. It was new in the box and had beautiful wood on it and I already had its "twin" at home. Its twin was also a beautifully stock Ruger #1-B in caliber 218 Bee! I scoped up the Hornet with a Leupold 6x18 variable scope (to match the 218 Bees scope!) and proceeded to do load development on the pretty little Hornet! Well load development took almost 3 years according to my loading log! I was ready to sell that Hornet dozens of times! But the lovely wood stock kept me after the secret load that would give me groups under 1 M.O.A.!!! Finally at the suggestion of a poster here on the internet I completely gave up on the plain brass I was using and went with Nickel Plated 22 Hornet brass along with the then relatively new Hornady 35 gr. V-Max bullets. Low and behold the lovely little Hornet perked up and I shot my first five shot group under 1 M.O.A. at 100 yards with it. That group measured .778" as a matter of fact and since then that Rifle has been allowed to go afield with me and has accounted for many Rock Chucks, Prairie Dogs, Ground Squirrels and various other small size Varmints! Do not ask me why the Hornet picked up accuracy wise when I changed to the tiny Hornady projectiles and Nickel Plated Brass - it just did! I am glad I did not "give up to soon" on that Hornet.

Well after a long days searching of western Montana yesterday for either a Ruger 77V in 204 or a Ruger #1-V SS or a Remington 700 VLS I have given up for this spring/summer and getting a 204 online for Prairie Doggin the season. I will wait for the Remington 700 VLS. I know how to do the triggers on these and all the ones of these I have are very accurate and I like the feel of them and their looks. I have a hunch Remington will make a run of all stainless and laminated stock 700 Varminters (700-VLSS's) in this caliber by next year. I have 3 of these all stainless 700 VLSS's already and really like their looks! The calibers I now have in this model are 17 Remington, 223 Remington and 22-250 Remington. I would really like to have one in 204 Ruger! It would be a hoot to see the name RUGER on the barrel of a Remington! Good for Ruger - introducing a new Rifle cartridge!

Hold into the wind

VarmintGuy

Varmit Guy
I am thinking a pac-nor barreled model 7. Speed lock firing pin and Hollands springs in the trigger after everthing gets a little polish. 4.5 to 14 luepold or I am really thinking about a Weaver V16. Just gotta pick the case. Probably go with an HS stock. I am ordering a High Tech blank for another green machine. I will have both so I can compare. When the 17AH gets done if the parts ever get here, I am goning to start get some parts together. 2005 is gonna be my year for the 20 cal.