Can this brass reforming be done?

[Naphtali]

Is there a procedure that reforms 7.62x51 and/or 308 Winchester brass to 358 Winchester that does not require fire forming or otherwise using consumables during the procedure? What I seek is a method where brass is sufficiently reshaped to allow 358 handloading to occur as though the case were originally 358.

I'm not concerned that the reformed brass might not "look" SAAMI. First firing accomplishes that. I'm trying to determine whether brass can be rendered "close enough" to be loaded as would actual 358 brass.

[jimkim]

I don't see any differences, between the two, other than neck diameter. Just run the cases through a 358win sizing die.

[Guesser]

I have several hundred new 358 cases that I don't need. If you are interested, PM me. All or part!!!!!!

[BerdanIII]

A tapered expander might make the job go easier. I chamfer the case mouths before I neck a case up; it makes the process go a little smoother and I also make sure I get a ring of sizing lube inside the case mouth.

You may need to square up the case mouths with a trimmer after sizing, too.

Back the sizing die off the shellholder a turn or two and try a reformed case in your rifle to see if it will chamber and allow the action to lock up. You can tailor your cases to the rifle this way and eliminate any excess headspace. For hunting loads, however, squish away since they have to got to chamber with no hesitation.

[S.R.Custom]

I don't see any differences, between the two, other than neck diameter. Just run the cases through a 358win sizing die.

I do this all the time using Lake City military brass. Just make sure the inside of the case necks are lubed first. Hornady One-Shot is perfect for this.

[jhrosier]

I made a bunch of .358 from 7.62 military brass with no problems.
I expanded the necks a bit with a tapered punch held in my drill press.
I have done it with the sizing die alone but the extra operation make them much easier to size.
I gave them a quick trim after to make sure that the case mouths were square.
I prefer to use the military brass rather then have incorrect commercial headstamps on the loaded ammo. Who knows where it will wind up when I am gone?

Jack

[mike in co]

slightly thinner neck ,,,,but its a common process
i have both new and reformed brass...and i have not built the rifle yet.

mike in co

[Wayne Smith]

If you find extreme difficulty or brass splitting at the neck learn to anneal before sizing and you will be good. If you want to do it in two steps get an 8mm expander button.

[jimkim]

If you find extreme difficulty or brass splitting at the neck learn to anneal before sizing and you will be good. If you want to do it in two steps get an 8mm expander button.

Good advice, I forgot to mention this.