.12 ga and .70 cups

[M.A.D]

I was at the range yesterday, and was looking at all the dumped 12 gauge high brass shells left on the ground,
It got me thinking, if i was to remove the plastic , would you be able to use the remaining cup as a jacket for 12 gauge and .700 jackets?
Might need a larger de rim die like they use for the 22 lr cases...
Sadly importing RCE cups is not an option...
Any thoughts? Do i need to take my tin foil hat off?

[Zbench]

The vast majority are steel these days, even if they look like brass, most are plated steel.

[bullet maker 57]

ZBench is right. Brass plated most likely.

[runfiverun]

and for sure there is a ring of steel under that rim.
otherwise the extractor would just rip right through hollow folded over brass that thin.

[seppos]

I would test it with magnet and cut it one in half. If there is no steel involved, why not draw it down to.. lets say regular caliber cups?

S

[William Yanda]

I know some bases are steel with a brass wash finish. I used the metal cup from a Federal Gold Medal hull for the ferrule on a chisel. I cannot say about a steel reinforcement in the rim, but the wall of the cup acted like brass in that application. You will have to cross section some and see.
Please let us know what you find.

[seppos]

Small test:
Winchester, Eley, Sellier Bellot and some old 12 gauge hulls: all get stuck to a magnet.
So it does not look very good in that sence.
Other question is how much will it affect to push a copper washed jacket thru a gunbarrel when some commercial manufacturers use that stuff in they loads. In shotgun the cup protects the barrel unless one uses only wad behind the slug.

S

[DanishM1Garand]

5/8ths copper pipe is around .680 OD. Fill a cut off chunk with molten lead then swage away. Anneal the copper pipe first though I'd think.

Ive never done it. Saw a guy on YouTube doing it.

[reed1911]

If you go the pipe method you will need to use either a closed cap piece or roll over the base of the cut pipe to form a base (a significant base, not just the edges). If you simply shoot a copper pipe piece filled with lead and swaged up, you run a vary big risk of the copper part lodging in the barrel and the lead being shot out, leaving a ring obstruction and very bad day if another shot is made.

[Ballistics in Scotland]

I'd be surprised if any are all brass nowadays. The modern shotgun shell was invented in the days of a relatively slow-moving extractor which contacted a rather wide section of the rim, in a double or single-shot gun. Nowadays any manufacturer would ask for trouble by turning out shells that will fail under the abrupt application of the small extractor of a semiautomatic.

If the plastic is all one piece, you would probably do better by removing the metal altogether, and using the plastic alone over some kind of solid wad. Running a grinder around the rim ought to do it.