Anybody make .257 Roberts brass from .30-06 brass? I have lots of .30-06 brass and I can't find brass for the .257 Roberts anywhere. I make lots of other cartridges from '06 so it shouldn't be too difficult. Tell me how you do it and then I will give you my ideas.
joe

No big problem. Easy. Steps. The parent of the .257 was the 7x57. '06 is 63mm long. 57 is 57 mm long. You are moving the neck back into thicker brass so may need to ream necks. What do you have? '06 into .270? .270 into 7x57? 7x57 into .257 full length die. Many combinations will work. The .308 family can be used but only 51 mm long so don't push in all the way.

Anneal is a good idea. Dip in molten, pure lead works o.k. Very, very good lube. I have taken 8x57 down to .22/250 (RCBS form die set). Bit of work but if you enjoy it. Luck. Happy trails.

I have made them from 25-06 but depending on your chamber you might have too thick necks. I did not anneal those made from 25-06 and did it in one step. Using steps like stated above will work; don't use too much lube or you will dent the shoulders. Lube sparingly at each step.

Thanks for the replies. I make 6.5x55, .25-06, 7x57, and 8x57 from .30-06. In each case, I use a Redding form and trim die to first take it down to the proper shoulder height and angle. After sawing off the excess brass and trimming to length, I run the brass through the proper full length sizing die. In making the 6.5x55, I first use the 7x57 form and trim die to basically take the brass down in two instead of one step. I then ream the inside diameter of the case while it is 7mm and then run it through the 6.5x55 form and trim, then FL size it. I have ordered a .257 Roberts form and trim die so I will make the .257 R brass the same way I make the 6.5x55 brass.
Though I haven't tried to make any .257 Rob brass yet, I'm sure this process will work fine.
Of course I anneal the .30-06 brass first.
joe

With all of those intermediate dies it should be pretty easy to make .257 Roberts from '06 brass. Actually, I see no need for a .257 form/trim die if you already have a 7x57 form/trim die. Form and trim in the 7x57 die first, then simply run those cases through your .257 FL die and you should be ready to roll. Of course, you'll need to check the thickness of the necks and thin them if needed, but most rifle chambers have necks that are rather too generous to begin with and your "thick-necked" brass may fit better than standard brass.

Along the lines of "Back in my day I used to have to milk the cows then walk four miles in the snow bare-footed to go to school", I've formed lots of .257 with nothing other than a .257 FL die. You'll lose and occasional case that way. But if you have any kind of intermediate die (8x57 with expander ball removed, 7x57, etc.) then by using a two-step process you will lose only a very small number of cases, if any. If you are skilled at annealing then your percentage success will be high.

I have a set of form dies made for that specific purpose if you are interested send a PM. I also have some nickel plated 257 Rbts brass (New)

I never buy form and trim dies; they are too expensive. I can buy a lot of brass for what those cost. I use plain full length sizing dies to make up whatever intermediate step I need.