Reforming brass

[ejh69]

Would like to make 7x57 and 257 Rob. brass from 270 Win. I would appreciate your input as to the correct steps I should take. Thanks in advance.

[pworley1]

You can also use 30 06. Make the 7X57 by annealing the neck then running the case through the sizing die with the stem removed. Be sure to use a good sizing lube sparingly. After sizing trim to length and fire form. Check the neck thickness, it may need to be turned. Once you have formed and fired the 7x57 you can repeat the process using the 7x57 to make the 257 Roberts.

[wallenba]

Whatever brass you use, start with this die http://www.midwayusa.com/product/524910/redding-trim-die-7x57mm-mauser-7mm-mauser?cm_vc=ProductFinding
It will make the next step, full length sizing easier on the brass. It won't size the neck beyond the 'fired' size of the desired caliber. This avoids an abrupt jump down in size and gives the opportunity to trim to desired length prior to FL sizing.
They make one for the 257 also http://www.midwayusa.com/product/512616/redding-trim-die-257-roberts?cm_vc=ProductFinding . They also make dedicated form and trim dies to make conversions in a lot of sizes, could not find one for the 7x57.

Be sure to lube the inside of the necks good when doing the final step of FL sizing. Because the neck brass will get a little thicker than normal, and between the die and expander things can get tight. It can even pull the shoulder up when extracting, or collapsing when going in. Just depends on the die and brass. I like to use the Lee case lube, because I can lube all the necks in advance, it still works after it dries, and won't affect the primers.
If you have a tight chamber, neck turning might be necessary too. This is just the way it goes sometimes when going from big to small.
You might try to find a smaller caliber to size up instead.

Try not to be intimidated by this process, after you do it, it gets simpler. Expect to ruin a little brass during the learning curve. It's not rocket science, just tedious.

[GRUMPA]

Boy this fits right up my alley. I do a lot of conversions, not as much as others might but I do a bunch of them. The 1 thing I would stress is to find the gauges for whatever your going to convert. Along with the gauges get an indicator so that you know without a doubt where the new gauge dimension is to the thousanths of an inch.

http://castboolits.gunloads.com/attachment.php?attachmentid=61836&d=1361389007

Some conversions require a lathe and some basic knowledge of machining, in the case of the 7x57 the only machining I suspect you'll want to do is reaming. People need to keep in mind when you alter the necks the thickness of the brass can and will change. Whenever you change ANYTHING on a case you have to be darn sure your the person in control and take NOTHING for granted.

Secondly I would initially use all the same head stamped brass, they can/will vary by who made them in the first place. Plan on annealing the necks, when a person changes things like shoulder location and neck diameter they weaken (more accurately it gets work hardened) the strength of the brass. Some more than others but like I said you have to be in control of what your doing and know the ins and outs of what's going on.

You should go in my page and just go through and read some of what I make. In there for the most part I ream the necks and anneal the cases, something that is rather important.

Grumpa (http://castboolits.gunloads.com/forumdisplay.php?117-Grumpa) <---Click that

I get PM's from folks wanting to know how to do something. Some things are rather easy and some do take a bit of work to make happen. I have a person inquiring about making 225 Winchester brass, which is something I personally haven't tried yet but I'm having him send me a few things and I'll give it a whirl and see what happens.

The 7x57 I would imagine is very similar to the 8x57 I do from 06 brass. Compared to what I convert those are rather simple to do in my mind.

The 1 thing that was mentioned already and very important is a very good lube. ME??...I make my own which is a mix of 50/50 Anhydrous Lanolin (RandyRat sells it) and Vaseline which works very well but just use it very sparingly.

[EDG]

The easiest way is to buy a good used RCBS trim dies off of Ebay. They should run no more than $15 each.
Fired .270 brass has a neck just right for 7X57. Just use the trim die to push the shoulder back.
Because the 7X57 normally has a large chamber neck it will not likely need the necks reamed or turned.
You can use a cut off 48 TPI hacksaw blade in a saber saw to cut the cases to rough length before trimming.

For .257 start with the 7X57 trim die then use the .257 trim die. Then cut to length. If you prefer you can reduce the lenght of the sized neck by cutting off first in the 7X57 die. Just wash all the cases to remove all the brass chips before sizing in the .257 die.
You need to investigate the neck diameter of your .257 chamber to determine if you need to turn or ream the necks.

To do this expand an old .257 case mouth with a tapered punch to about .015 over the neck diameter of a .257 loaded round. You should just put a little funnel mouth on the case. Chamber it and shove home with the bolt and extract.
Measure the case mouth diameter after it has been squashed back down by the chamber.

Make a .257 case from your .270 brass and seat a bullet in it. If the loaded .257 (from .270 case) neck is larger than the chamber neck you have to reduce the brass thickness. The chamber neck needs at least .002 clearance and probably .003 is better for hunting ammo.

After you form the cases with a trim die and cut them to lenght they still need to be FL sized in a regular size die.

If you happen to go this way you need to anneal the finished cases to insure long life of the case neck.


If you want to try this on for size - no pun intended you can remove the decapping rod from your FL dies.

Use the 7X57 to form a case
then form the 7X57 case to .257 in the .257 die.

You will have to figure out the best way to cut the extra material off.

If you have other shorter trim dies you can often use them for the trimming operations.
A .308 trim die will work for cutting off many different cases before final forming and sizing.

[Char-Gar]

Start with either an RCBS or Redding file trim die in the caliber of the finished case. There is a difference in these makes of dies. The RCBS will full length resize the case and the Redding will not size the cases. When case formings you will need to full length resize the case at the final step.

Run the parent case into the die and cut off the excess with a fine tooth hacksaw and dress the case mouth down to the surface of the die with a double cut file. The die is hardened, so the die won't be damaged by the file. Deburr the case mouth inside and out.

Imperial case sizing wax is made for this kind of job and works very well, although I find it inferior as a general case lube. If you don't lube the case, it will stick in the die.

You will get better results and less shoulder dents if you run the case into the die until you feel the pressure, back it down give it a 1/3 turn and do it again. Repeat until the case is fully into the die. Do it in one stroke and many cases will have dents, folds and creases in them.

Now run the finished case through a full length sizing die to finish the task and expand the neck.

If you want to anneal the case, now is the time to do it. It will remove the hardness induced by the working of the brass. Anneal before you case form and there is a good chance you will collapse the case.

I check the final produce in a Wilson guage just to be sure everything is up to spec and then load and fire.

I have made many thousand 308, 300 Savage, 8 X57, 7 X 57, 9 X 57, 6.5 X 57, 6.5 X 55 and 270 cases from USGI 30-06 brass. At one time, I had ten gallons of once fired 1954 Lake City cases.

[ejh69]

I really appreciate all your inputs. I think I am well on my way. Thanks

[Reg]

Lot of good info here to help you convert the brass but the one thing to keep in mind when converting a bigger case to a smaller is that in many cases you have a slightly reduced inner capacity due to thicker brass in one area or another and you should reduce your loads a bit to prevent creating excessive pressures.