Forming 6XC Brass - Picture

[Ledd Slinger]

Unfortunately no matter which case you use to form 6XC, (22-250, 308 family, or 6.5 CM) youre gonna end up with either shoulder or body brass in the neck. as long as you give it a good annealing and proper neck turning down onto the shoulder with the correct 30 degree cutter, you shouldn't have to worry about donut formation.

As for the formed 308 case, the measured dimensions match exactly to the 6XC case dimensions. So no fire forming is 'needed'. Other than thicker brass in the neck, a properly formed 308 case is just the same as brass from Norma with the 6XC head stamp. Maybe even better because when forming you can control where you set the shoulder headspace and make it match your chamber to exactly where you want it.

The base diameter of my formed cases measure exactly .4660" and the shoulder diameter measures exactly .4505". That is DEAD ON for listed 6XC case dimensions. And I have my headspace set .002" off. They chamber beautifully and again, there is NO fire forming needed because my headspacing is already set.

 

[spclark]

I have so far made my 6XC cases from Lapua 22-250 cases, but am interested in this process.
If I'm reading correctly, any 308 based case should work. (243, 260, 7mm08)??

Has anyone experimented with 308 Palma yet to have the small primer pocket??

Yes sir. Any 308 family case will work exactly the same so it leaves a lot of options out there for commonly available brass from all different manufacturers.

Yep, that's what I believed to be true when I took a fresh box of Lapua's PALMA brass a couple of years ago & embarked upon a quest to make 6XC cases, see if any benefit was to be had from the small primer pockets MOSTLY for longer case life / more reloads before primers wouldn't stay in.

It can be done, it's just not easy to avoid things like folded-up shoulders and / or having to inside-ream necks when you're close to 6mm neck OD owing to the considerable thickening that happens when you squeeze a 0.0145" .308-size neck wall down to something more like 0.017"+ @ 6mm.

I had a Tubb-sourced sizing die back then so using his shoulder+neck bushing style bump gauge bushing (generously oversized neck ID) to push the shouders back incrementally helped avoid folded shoulders for the most part.

Having sold that die set I found a 6.5x47 die works just as well for the intermediate sizing steps, then switching to a regular bushing-style sizing die for the final neck shaping requires using two bushings on so-far untrimmed brass otherwise the necks are too long to fit the die. The second bushing is oversize compared to the bushing you insert first, the extra one is just a spacer.

Anyway, the finished Palma>6XC brass loads & shoots (for me) identical to the Norma factory stuff (Tubb had some new stuff recently!!) & when necks are trimmed to the 0.011" thickness I find I prefer for my 6mm cartridges weighs virtually the same too.

Oh, and they do seem to be lasting longer. Loaded for 600 and 1,000 yards I've fired some of this batch seven times & pockets are still tight. With the Norma cases I felt I was lucky if I could get four....

 

[Ledd Slinger]

***UPDATE***

I just got done running neck thickness tests with seated bullets.

First I tried a 6XC case formed from a piece of Federal 243 Win brass. Next I used a case formed from Black Hills Match 308 Win.
NECKS HAVE NOT BEEN TURNED. Measurements are as follows.

Federal 243 Win : 0.273"
BHA Match 308 : 0.273"

Both were exactly the same diameter with unturned necks. My chamber is a NO TURN neck at 0.275" so both rounds chambered perfectly with bullets seated. Looks like I won't even have to turn down my necks. Just clean up any pieces that show high spots on the concentricity gauge and I'm Ready to rock

 

[mysticplayer]

That saves a bunch of work but 15 thou thick necks in a 6mm?

I am down at 10 thou and it is shooting great.

Oh, 1 final difference. Assume you have a shorten your cases a bunch to get to 1.89" length? Never been a fan of grinding down alot of extra case length but if there is the machinery to do it..... no biggie.

The 22-250 end up at the correct length after COW forming so I do not need to trim. I also wouldn't need to outside neck turn in your chamber but mine is smaller which I prefer as I really like the thinner neck in this cal.

Also, so far with the PRVI brass, no donuts. Now I would expect that normally as some of the shoulder is being squished into the necks but zippo with the current lot. So I saved another step.

Potato... Patatoe.. All good fun and more 6XC's being shot by happy shooters.

Jerry

 

[Ledd Slinger]

Yeah you definitely have to take some length off the necks. Pretty much the only downside to this process I have found. I just buzz the necks with a dremel cutting wheel and finish them up in a case trimmer. I made up a hand held drill adapter for one of my trimmers which also makes things fast.
Plan on rigging up something in the future to hold multiple cases on my chop saw table and hit them with a metal cutting blade all at once.

As far as the 15 thou necks are concerned, I personally don't mind it. Sure neck tensions won't be as consistent, but my 6XC is just a hunting/varmint rifle. I'll anneal every 2-3 firings to keep them on the softer side, but with only .001" outward flex around the circumference of the neck wall, they should stay workable for a long time at any pressure.

On another note. After deciding to build this rifle, I originally intended to use 22-250 brass for forming. But when I saw the price difference between 308 vs 22-250 brass in any condition, I started doing some more research. I paid $30 shipped for 115 308 Match Grade brass cases once fired from Black Hills factory ammo. Next I picked up another 100 pieces of once fired Federal 243 brass for about $20 plus shipping. Then I had some more 243 brass laying around that I used to make 260 brass with. You could also buy Lake City brass for really cheap if you wanted.
Not sure why, but 22-250 brass is getting more and more expensive. So its really a win-win here. I get a better formed case and at a cheaper price point. Not trying to knock the 22-250 method too bad, but I'll never try it after seeing how cheap and easy the 308 family case method works with the 7mm-08 die.

 

[dearlallen]

I have been watching this thread with great interest as I have recently formed some
WW 22-250 cases to the 6XC. Fireformed with the COW method and now have fired
full powered rounds in them. Seem to work really well, however…After some measurements just in front of the extractor groove, they are somewhat smaller
than the Norma 6XC brass I have and don't equal the 6XC in size until about .200
in front of the extractor groove. Not sure if this is going to be a problem but I'm thinking the primer pockets may loosen prematurely especially since these pockets didn't feel all that tight even when new. Any 6XC experts care to comment?
Sure would like to hear some thoughts on this.

Regards, John.

My suggestion would be to use Russian primers. They are very consistent and are a bit oversized.

 

[cfreeman]

For those of you using PRVI 22-250 brass, how does it compare to the Norma 6xc Brass? I was looking at this, as the brass I usually use besides Norma, Winchester, is frickin unobtanium right now.

I was planning on using the Tubb die to reform, just because that's what I have.

Thanks

 

[JAnderson94]

With this method of forming do you get donuts at the neck/shoulder junction? I tried resizing some palma brass to 243 then put it in my 6xc FL sizing die and did 3/8th of a turn at a time. Needless to say not very impressed with what my results where and looking for a new style to try. If I could just get away with neck turning I would be a happy camper!

 

[Ledd Slinger]

With this method of forming do you get donuts at the neck/shoulder junction? I tried resizing some palma brass to 243 then put it in my 6xc FL sizing die and did 3/8th of a turn at a time. Needless to say not very impressed with what my results where and looking for a new style to try. If I could just get away with neck turning I would be a happy camper!

Can't do that. You will crush and/or fold a shoulder doing it that way. Trust me, I tried that first out of curiosity. If you do it exactly the way I explained with a shortened 7mm-08 'body' die, I guarantee you will have perfectly formed brass.

As far as donuts, none from forming. Will have to shoot it to be sure. But in my situation where I don't have to neck turn, I doubt I'll have trouble with donuts

 

[JAnderson94]

With this method of forming do you get donuts at the neck/shoulder junction? I tried resizing some palma brass to 243 then put it in my 6xc FL sizing die and did 3/8th of a turn at a time. Needless to say not very impressed with what my results where and looking for a new style to try. If I could just get away with neck turning I would be a happy camper!

Can't do that. You will crush and/or fold a shoulder doing it that way. Trust me, I tried that first out of curiosity. If you do it exactly the way I explained with a shortened 7mm-08 'body' die, I guarantee you will have perfectly formed brass.

As far as donuts, none from forming. Will have to shoot it to be sure. But in my situation where I don't have to neck turn, I doubt I'll have trouble with donuts

I did get away without crushing shoulders, that's why I was limited to 3/8th of a turn after I made contact with the case in the 6XC FL die. Any more and I started to crush. A cross section of the final piece showed a very thick wall and a "rounded" neck shoulder junction on the outside with a donut in the inside as well...

 

[Ledd Slinger]

Yeah trying to push the shoulder back at a 30 degree angle that far through a hole meant for a 6mm neck is just way too much. The outcome would be unpredictable as the brass would be under way too much stress.

 

[Raptor]

How much neck run out are you getting on your cases doing this?? I do about the same thing for 6.5 Creedmoor brass and I get about half of them with .008+ run out on the necks. Just wondering how that will affect my accuracy on the fist firing. Thanks guys!!

 

[Ledd Slinger]

How much neck run out are you getting on your cases doing this?? I do about the same thing for 6.5 Creedmoor brass and I get about half of them with .008+ run out on the necks. Just wondering how that will affect my accuracy on the fist firing. Thanks guys!!

Havent checked runout or neck wall concentricity yet. I'm actually curious about that myself. I will do that when I get home on Friday and post my results for you.

 

[Mudcat]

Maybe I have spent the last decade making things too difficult on myself but I just take a piece of Winchester 22-250, run it through a 6xc die like I would if I was FL sizing it, prime it, drop in the usual amount of powder, stick a bullet on top and then go shoot the thing. Out to at least 300 yards, they work just fine. We fireform ours during practice or short course matches. Why waste a bullet, powder, or bbl life? When sized they jget just the hint of a "mushroom head" and feed just fine during rapid fire in a T2k from the mag. The other nice thing about Win brass is that you dont get the doughnut, ever. I still have a batch I formed back in 2006 that I am still shooting today, some with over 20 firings on them.

 

[Ledd Slinger]

I have actually found that many different calibers requiring firforming actually shoot really well during that process and I will often start load testing while fire forming. Like I stated earlier, my original plan was to use 22-250 brass, but when I saw that it was difficult to find and the price was getting a little high for it, I began researching other ideas. This is what I came up with from borrowing bits and pieces of info from others. Not saying that there is anything wrong with using 22-250 brass, but with my method you can utilize much cheaper brass and you have a fully formed case right off the bat. Does my method take longer to make a 6XC case? Sure it does, but not that much longer. Plus having the option of using Lapua 308 Palma brass can be seen as an advantage to those who want to push the upper limits of pressures.

 

[Changeling]

Hi LS. I have really enjoyed reading this posting and your forming method.

I get the feeling though that you don't think this formed brass would be great/awesome for competition, but just hunting.
I really believe your method would make some awesome competition brass because you haven't stressed the brass as some of the other ways of forming this case does.
One would of course have to prep the brass for competition as usual, especially turning the necks.
Just my opinion.

 

[Ledd Slinger]

I think it could be competition worthy in the right rifle. A tight neck chamber would have to made a bit larger than with actual 6XC brass from Norma or brass formed from 22-250 because the necks may have to remain a little thicker I think. My neck walls are 15 thou with the Winchester made BHA brass, but if a person could turn it down to about 13 thou and using a .271 to .273 neck chamber, it may work for decent consistency on neck tension. Turning anymore than that may be a pain without a lathe setup and the risk of a bad donut becomes more probable if not watched closely and touched up from time to time.

Of course this is all just a guess I am making. Perhaps my brass will shoot with excellent accuracy the way it is. And perhaps my assumptions on neck tension and donuts will prove to be a farce with neck turned brass. But that remains to be seen...

I will be ordering the 21st century lathe setup to compliment the 21st century neck turner I already own. It should make things much faster and easier.

 

[Ledd Slinger]

Ok, so I just did a quick test on the formed, trimmed, and sized 6XC cases for neck wall concentricity and runout on the neck of the brass.

Tools used: Redding Concentricity gauge for neck walls and RCBS Case Master for runout.

The largest deviance in neck wall thickness I found was just a hair over 0.001" (about .00125") and the worst case neck for runout was just a little over 0.002". Surely some of the runout was caused by the neck wall deviations because the necks are not turned yet.

The average neck wall deviance was about +/-.001" from zero, but I did have one that was nearly perfect. Keeping in mind that the necks are not turned yet, I found this to be quite surprising.

The average runout on the case necks with no bullet seated and running them through a floating expander ball stem was .001" with the one case being just a hair over .002". Probably about .00220" to be exact.

Cases were both formed and sized on an RCBS Rockchucker press. When the rifle is ready to shoot, I will seat the bullets with my Forster Coax press and check runout on the bullet as well.

Of course these were only 5 random cases I grabbed out of the pile. Doesn't really prove anything. There will be cases to cull I'm sure. But it definitely showed that the random 5 pieces I grabbed were extremely consistent in both measurements and that this process of forming is very precise indeed. Hope this helps to alleviate any doubts with this process. Take care.

 

[jkl]

I just finished making 30 cases they are ready to fire form. I will post how it works after fire forming.

John

 

[Ledd Slinger]

I just fonoshed making 30 cases they are ready to fire form. I will post how it works after fire forming.

John

Which parent case? 308? If you made them the way I explained from a 308 family case, theres no need for fire forming. Just load and start shooting.